Toyota Avalon (XX50): Power Steering System(for Hv Model)

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Steering / Power Assist Systems / Power Steering System(for Hv Model)

Torque Sensor1 (C1511-C1514,C1517,C1521-C1523,C1528,C1531-C1555)

DESCRIPTION

While torque sensor system, motor system or ECU system malfunctions are detected, the fail-safe function suspends power assist. However, power assist continues with limited assistance amount if only C1533 or C1534 is output.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1511	Torque Sensor1	Torque sensor malfunction	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1512	Torque Sensor2	Torque sensor malfunction	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1513	Torque Sensor Deviation Excessive	Torque sensor malfunction	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1514	Torque Sensor Power Supply Voltage	Torque sensor malfunction	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1517	Torque Hold	Torque sensor malfunction	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1521	Short in Motor Circuit	Motor overcurrent	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1522	Power Supply Sensor	Motor current sensor malfunction	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1523	Current Deviation Excessive	Excessively large current deviation	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1528	Motor Rotation Angle Sensor	Motor rotation angle sensor malfunction	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1531	ECU Malfunction	ECU internal malfunction (CPU malfunction)	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1532	ECU Malfunction	ECU internal malfunction (Peripheral circuit malfunction)	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1533	Temperature Sensor Circuit is Low or High	ECU internal malfunction (Substrate temperature sensor malfunction)	Rack and pinion power steering gear assembly	EPS warning light: Comes on	The ECU judges the system has returned to normal	-
C1534	EEPROM	ECU internal malfunction (EEPROM error)	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1555	Motor Relay Welding Failure	Motor relay circuit malfunction	Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here

PROCEDURE

1.	CHECK FOR DTC

(a) Clear the DTCs.

Chassis > EMPS > Clear DTCs

(b) Check for DTCs.

Chassis > EMPS > Trouble Codes

Result	Proceed to
DTCs other than C1511, C1512, C1513, C1514, C1517, C1521, C1522, C1523, C1528, C1531, C1532, C1533, C1534 or C1555 are not output.	A
DTCs other than C1511, C1512, C1513, C1514, C1517, C1521, C1522, C1523, C1528, C1531, C1532, C1533, C1534 or C1555 are output.	B
DTCs are not output.	C

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

GO TO DIAGNOSTIC TROUBLE CODE CHART

USE SIMULATION METHOD TO CHECK

Torque Sensor Zero Point Adjustment Undone (C1515)

DESCRIPTION

This DTC does not indicate a malfunction. The power steering ECU (rack and pinion power steering gear assembly) stores this DTC when it determines that torque sensor zero point calibration has not been performed.

When the IG terminal voltage is below 8 V, torque sensor zero point calibration cannot be performed.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1515	Torque Sensor Zero Point Adjustment Undone	This DTC is stored when torque sensor zero point calibration has not been performed.	Torque sensor zero point calibration	EPS warning light: Comes on	Zero point calibration is performed or the power switch is turned on (IG) again	There is no malfunction if this DTC is not output again after performing zero point calibration.

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here

PROCEDURE

1.	CHECK FOR DTC

(a) Calibrate the torque sensor zero point. (Step 1)

Chassis > EMPS > Utility

Tester Display
Torque Sensor Adjustment

(b) Check for DTCs. (Step 2)

Chassis > EMPS > Trouble Codes

HINT:

If DTCs are output, perform steps (1) and (2) two more times.

Result	Proceed to
DTCs are still output after performing steering zero point calibration 3 times.	A
Normal system code is output.	B

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

END

Torque Sensor Zero Point Adjustment Incomplete (C1516)

DESCRIPTION

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1516	Torque Sensor Zero Point Adjustment Incomplete	Torque sensor zero point calibration is incomplete due to the steering wheel being touched during calibration.	Torque sensor zero point calibration	EPS warning light: Comes on	The DTC is cleared	There is no malfunction if this DTC is not output again after clearing the DTC and torque sensor calibration value, and performing zero point calibration.

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here

PROCEDURE

1.	REPLACE CHECK FOR DTC

(a) Clear the DTCs. (Step 1)

Chassis > EMPS > Clear DTCs

(b) Calibrate the torque sensor zero point. (Step 2)

Chassis > EMPS > Utility

Tester Display
Torque Sensor Adjustment

Chassis > EMPS > Trouble Codes

HINT:

If DTCs are output, perform steps (1) to (3) two more times.

Result	Proceed to
DTCs are still output after performing steering zero point calibration 3 times.	A
Normal system code is output.	B

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

END

Vehicle Speed Signal (C1541)

DESCRIPTION

The power steering ECU (rack and pinion power steering gear assembly) receives vehicle speed signals from the skid control ECU (brake booster with master cylinder assembly) via CAN communication. The ECU provides appropriate assist force in accordance with the vehicle speed based on the signals.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1541	Vehicle Speed Signal	A vehicle speed signal malfunction is detected	Brake control system CAN communication system	EPS warning light: Comes on	The ECU judges the system has returned to normal	-

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here

PROCEDURE

1.	CHECK CAN COMMUNICATION SYSTEM

(a) Check if DTC U0129 is output.

Chassis > EMPS > Trouble Codes

Result	Proceed to
DTC U0129 is not output.	A
DTC U0129 is output.	B

GO TO BRAKE CONTROL SYSTEM (DIAGNOSTIC TROUBLE CODE CHART)

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

IG Power Supply Voltage (C1551)

DESCRIPTION

When a malfunction is detected in the power source circuit, the fail-safe function suspends power assist.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1551	IG Power Supply Voltage	When the PIG power supply voltage is normal, the IG power supply voltage is 18.5 V or higher	Harness or connector Rack and pinion power steering gear assembly	EPS warning light: Comes on	The ECU judges the system has returned to normal	-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.
Click here
Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - RACK AND PINION POWER STEERING GEAR ASSEMBLY)

(a) Disconnect the C67 rack and pinion power steering gear assembly connector.

Front view of wire harness connector

(to Rack and Pinion Power Steering Gear Assembly)

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
C67-4 (IG) - Body ground	Power switch on (IG)	Below 18.5 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.	CHECK FOR DTC

(a) Clear the DTCs.

Chassis > EMPS > Clear DTCs

(b) Check for DTCs.

Chassis > EMPS > Trouble Codes

Result	Proceed to
DTC is output.	A
DTC is not output.	B

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

USE SIMULATION METHOD TO CHECK

PIG Power Supply Voltage (C1552,C1554)

DESCRIPTION

When a malfunction is detected in the PIG power source and power supply relay system, the fail-safe function suspends power assist.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1552	PIG Power Supply Voltage	PIG power source circuit malfunction	EPS fuse Harness or connector Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1554	Power Supply Relay Failure	Power source relay circuit malfunction	EPS fuse Harness or connector Rack and pinion power steering gear assembly	EPS warning light: Comes on	Power switch is turned on (IG) again	-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.
Click here
Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (RACK AND PINION POWER STEERING GEAR ASSEMBLY - BODY GROUND)

(a) Disconnect the C67 rack and pinion power steering gear assembly connector.

Front view of wire harness connector (to Rack and Pinion Power Steering Gear Assembly)

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
C67-8 (PIG) - Body ground	Always	9 to 16 V

Standard Resistance:

Tester Connection	Condition	Specified Condition
C67-7 (PGND) - Body ground	Always	Below 1 Ω

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

Error in Matching of ECUs (C1567)

DESCRIPTION

The power steering ECU (rack and pinion power steering gear assembly) determines whether an incompatible hybrid vehicle control ECU, main body ECU (multiplex network body ECU) or skid control ECU (brake booster with master cylinder assembly) is installed based on the identification information.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1567	Error in Matching of ECUs	An incompatible hybrid vehicle control ECU is detected An incompatible main body ECU (multiplex network body ECU) is detected An incompatible skid control ECU (brake booster with master cylinder assembly) is detected	Incorrect hybrid vehicle control ECU Incorrect main body ECU (multiplex network body ECU) Incorrect skid control ECU (brake booster with master cylinder assembly) Rack and pinion power steering gear assembly	EPS warning light: Comes on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here

PROCEDURE

1.	CHECK RELATED PART

(a) Confirm if the related part has the correct part number.

Related Part	Hybrid vehicle control ECU
	Main body ECU (Multiplex network body ECU)
	Skid control ECU (Brake booster with master cylinder assembly)

NOTICE:

When removing the related part to check it, be sure to follow the appropriate procedures and precautions.

Hybrid vehicle control ECU
Click here
Main body ECU (Multiplex network body ECU)
Click here
Skid control ECU (Brake booster with master cylinder assembly)
Click here

Result	Proceed to
The related part has the correct part number.	A
The related part has an incorrect part number.	B

GO TO STEP 3

2.	CHECK FOR DTC

(a) Select Health Check on the Techstream screen and check if system DTCs of the related part are output.

HINT:

If system DTCs of the related part are stored, assist map writing to the power steering ECU (rack and pinion power steering gear assembly) may not be performed properly.

Result	Proceed to
System DTCs of the related part are output.	A
System DTCs of the related part are not output.	B

GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

3.	REPLACE RELATED PART WITH PART THAT HAS CORRECT PART NUMBER

(a) Replace the related part with one that has the correct part number.

Hybrid vehicle control ECU
Click here
Main body ECU (Multiplex network body ECU)
Click here
Skid control ECU (Brake booster with master cylinder assembly)
Click here

4.	CHECK FOR DTC

(a) Check for DTCs.

Chassis > EMPS > Trouble Codes

Result	Proceed to
DTCs are not output.	A
DTCs are output.	B

END

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

Assist Map Number Un-Writing (C1581)

DESCRIPTION

This DTC will be stored if the power steering ECU (rack and pinion power steering gear assembly) determines that the assist map is not written in the ECU.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1581	Assist Map Number Un-Writing	Assist map not written in power steering ECU (rack and pinion power steering gear assembly)	CAN communication system Hybrid vehicle control ECU Main body ECU (Multiplex network body ECU) Skid control ECU (Brake booster with master cylinder assembly) Rack and pinion power steering gear assembly	EPS warning light: Comes on	Assist Map Writing is performed or the power switch is turned on (IG) again	-

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here

HINT:

Related parts store information necessary for assist map writing.

Related Part:

Hybrid vehicle control ECU
Main body ECU (Multiplex network body ECU)
Skid control ECU (Brake booster with master cylinder assembly)

PROCEDURE

1.	PERFORM ASSIST MAP WRITING

(a) Perform assist map writing.

Chassis > EMPS > Utility

Tester Display
Signal Check

(b) Check for DTCs.

Chassis > EMPS > Trouble Codes

Result	Proceed to
DTC C1581 is output.	A
DTC C1581 is not output.	B

END

2.	CHECK CAN COMMUNICATION SYSTEM

(a) Check for DTCs.

Click here

Result	Proceed to
CAN communication system DTCs are not output.	A
CAN communication system DTCs are output.	B

GO TO CAN COMMUNICATION SYSTEM

3.	CHECK RELATED PART

(a) Confirm if the related part has the correct part number.

Related Part	Hybrid vehicle control ECU
	Main body ECU (Multiplex network body ECU)
	Skid control ECU (Brake booster with master cylinder assembly)

NOTICE:

When removing the related part to check it, be sure to follow the appropriate procedures and precautions.

Hybrid vehicle control ECU
Click here
Main body ECU (Multiplex network body ECU)
Click here
Skid control ECU (Brake booster with master cylinder assembly)
Click here

Result	Proceed to
The related part has the correct part number.	A
The related part has an incorrect part number.	B

GO TO STEP 5

4.	CHECK FOR DTC

(a) Select Health Check on the Techstream screen and check if system DTCs of the related part are output.

HINT:

If system DTCs of the related part are stored, assist map writing to the power steering ECU (rack and pinion power steering gear assembly) may not be performed properly.

Result	Proceed to
System DTCs of the related part are output.	A
System DTCs of the related part are not output.	B

GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

5.	REPLACE RELATED PART WITH PART THAT HAS CORRECT PART NUMBER

(a) Replace the related part with one that has the correct part number.

Hybrid vehicle control ECU
Click here
Main body ECU (Multiplex network body ECU)
Click here
Skid control ECU (Brake booster with master cylinder assembly)
Click here

6.	CHECK FOR DTC

(a) Check for DTCs.

Chassis > EMPS > Trouble Codes

Result	Proceed to
DTCs are not output.	A
DTCs are output.	B

END

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

Assist Map Number Mismatch (C1582)

DESCRIPTION

When an incorrect hybrid vehicle control ECU, main body ECU (multiplex network body ECU) or skid control ECU (brake booster with master cylinder assembly) is installed after the assist map has been written to the power steering ECU (rack and pinion power steering gear assembly), DTC C1582 is stored because the information stored in the power steering ECU (rack and pinion power steering gear assembly) does not match the vehicle specifications.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C1582	Assist Map Number Mismatch	Assist map number mismatch	CAN communication system Incorrect hybrid vehicle control ECU Incorrect main body ECU (multiplex network body ECU) Incorrect skid control ECU (brake booster with master cylinder assembly) Rack and pinion power steering gear assembly	EPS warning light: Does not come on	Assist Map Writing is performed or the power switch is turned on (IG) again	-

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here

HINT:

Related parts store information necessary for assist map writing.

Related Part:

Hybrid vehicle control ECU
Main body ECU (Multiplex network body ECU)
Skid control ECU (Brake booster with master cylinder assembly)

PROCEDURE

1.	CHECK CAN COMMUNICATION SYSTEM

(a) Check for DTCs.

Click here

Result	Proceed to
CAN communication system DTCs are not output.	A
CAN communication system DTCs are output.	B

GO TO CAN COMMUNICATION SYSTEM

2.	CHECK RELATED PART

(a) Check if the part below has been replaced with an incorrect part in the past.

Related Part	Hybrid vehicle control ECU
	Main body ECU (Multiplex network body ECU)
	Skid control ECU (Brake booster with master cylinder assembly)

NOTICE:

When removing the related part to check it, be sure to follow the appropriate procedures and precautions.

Hybrid vehicle control ECU
Click here
Main body ECU (Multiplex network body ECU)
Click here
Skid control ECU (Brake booster with master cylinder assembly)
Click here

(b) When DTC C1582 is output and parts have not been exchanged, replace the power steering ECU (rack and pinion power steering gear assembly) as it may have an internal malfunction.

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing.

Click here

Result	Proceed to
The related part has an incorrect part number.	A
The related part has the correct part number, or a related part and rack and pinion power steering gear assembly have not been replaced.	B

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

3.	REPLACE RELATED PART WITH PART THAT HAS CORRECT PART NUMBER

(a) Replace the related part with one that has the correct part number.

Hybrid vehicle control ECU
Click here
Main body ECU (Multiplex network body ECU)
Click here
Skid control ECU (Brake booster with master cylinder assembly)
Click here

4.	CHECK FOR DTC

(a) Check for DTCs.

Chassis > EMPS > Trouble Codes

Result	Proceed to
DTCs are not output.	A
DTCs are output.	B

END

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

Calibration

CALIBRATION

TORQUE SENSOR ZERO POINT CALIBRATION (USING TECHSTREAM)

NOTICE:

Perform torque sensor zero point calibration if any of the following conditions occur:

The rack and pinion power steering gear assembly has been replaced.
There is a difference in steering effort between turning left and right.

(a) Perform inspection before calibration.

(1) Turn the power switch off.

(2) Connect the Techstream to the DLC3.

(3) Turn the power switch on (IG).

(4) Turn the Techstream on.

(5) Calibrate the rack and pinion power steering gear assembly. Enter the following menus: Chassis / EMPS / Data List.

(6) Read the Data List according to the display on the Techstream.

Chassis > EMPS > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

IG Power Supply

IG power source voltage

Min.: 0.0000 V

Max.: 20.1531 V

8 to 16 V

Power switch on (IG)

Chassis > EMPS > Data List

Tester Display
IG Power Supply

Standard Voltage:

8 to 16 V

NOTICE:

If the IG power supply voltage is 8 V or less, calibration cannot be performed. In this case, charge or replace the auxiliary battery, and then perform calibration.

(b) Perform torque sensor zero point calibration.

NOTICE:

If DTC C1516 (Torque Sensor Zero Point Adjustment Incomplete) is stored, the torque sensor zero point cannot be calibrated. Clear the DTCs before starting calibration.

(1) Align the front wheels straight ahead and center the steering wheel.

(2) Turn the power switch off.

(3) Connect the Techstream to the DLC3.

(4) Turn the power switch on (IG).

(5) Turn the Techstream on.

(6) Enter the following menus: Chassis / EMPS / Utility / Torque Sensor Adjustment.

Chassis > EMPS > Utility

Tester Display
Torque Sensor Adjustment

NOTICE:

Do not turn the steering wheel sharply.
During the torque sensor zero point calibration the steering wheel will shudder. Do not touch the steering wheel until at least 3 seconds have elapsed after the shuddering has stopped.

(7) Check for DTCs.

Chassis > EMPS > Trouble Codes

NOTICE:

If DTC C1515, C1516, C1534 or C1581 is output, perform troubleshooting for the corresponding DTC.

Result	See Procedure
DTC C1515 is output.
DTC C1516 is output.
DTC C1534 is output.
DTC C1581 is output.

ASSIST MAP WRITING (USING TECHSTREAM)

NOTICE:

Perform assist map writing if the following condition occurs:

The rack and pinion power steering gear assembly has been replaced.

(a) Turn the power switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / EMPS / Utility / Signal Check.

Chassis > EMPS > Utility

Tester Display
Signal Check

HINT:

Follow the instructions on the Techstream to perform Signal Check.
With DTC C1581 output, performing Signal Check will cause the rack and pinion power steering gear assembly to enter Signal Check and the assist map will be written automatically.

(f) Wait for at least 5 seconds.

(g) Check for DTCs.

Chassis > EMPS > Trouble Codes

HINT:

After writing the assist map, if DTC C1581 is output, perform the troubleshooting procedure for DTC C1581.

Click here

Check Assist Limit Record

CAUTION / NOTICE / HINT

HINT:

Perform this troubleshooting procedure when no DTCs are output, including DTCs related to CAN communication system malfunctions.

PROCEDURE

1.	READ VALUE USING TECHSTREAM (ASSIST LIMIT RECORD 1)

(a) Using the Techstream, read the Data List item "Assist Limit Record 1".

Click here

Chassis > EMPS > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Assist Limit Record 1	Information of assist limit that was used in the past or is currently in use (latest history)	Unrec, Mtr Overheat, Pow Vol Low, Pow Vol Low Prevent, Eng Stall, Ready OFF, Mtr Overload, DC-DC Malf, Vhcl Spd Sig Malf, Batt Vol Keep	-	-

HINT:

For the Data List item "Assist Limit Record 1", each item in the Range is described below.

	Range	Description	Diagnostic Note
Assist Limit Record 1	Unrec	No assist limit. Continue with troubleshooting for "Heavy steering".	-
	Mtr Overheat	When the vehicle is stopped or traveling at low speed, and steering operations are performed repeatedly or the steering wheel is turned all the way to the side and held there for a long time, assist may be limited in order to prevent overheating of the power steering motor assembly and power steering ECU assembly. After 10 minutes elapse with the power switch on (READY) and no steering operations being performed, the system will return to normal. After recovering from the overheated condition, assist can be performed as usual.	-
	Pow Vol Low	When insufficient auxiliary battery charge, or auxiliary battery degradation etc. causes the voltage to temporarily decrease, assist may be stopped. After the auxiliary battery condition returns to normal, assist can be performed as usual.	-
	Pow Vol Low Prevent	When insufficient auxiliary battery charge, or auxiliary battery degradation etc. causes the voltage to temporarily decrease, assist may be limited. After the auxiliary battery condition returns to normal, assist can be performed as usual.	-
	Eng Stall	When the engine stalls, auxiliary battery charge becomes insufficient, so assist is stopped. After recovering from the engine stall, assist can be performed as usual.	Not displayed for this vehicle
	Ready OFF	After Ready ON, if a malfunction in the HV system etc. causes a return to Ready OFF, the HV battery charge becomes insufficient, so assist is stopped. After returning to Ready ON state, assist can be performed as usual.	-
	Mtr Overload	When the steering wheel cannot turn, such as when a road wheel is against a curb, if the driver continues to apply force to the steering wheel, current to the motor may be limited to prevent overheating. When the steering wheel is returned to a neutral position, assist can be performed as usual.	-
	DC-DC Malf	If there is a malfunction in the DC-DC converter, etc., assist may be limited. After the DC-DC converter returns to normal, assist can be performed as usual.	Not displayed for this vehicle
	Vhcl Spd Sig Malf	If the vehicle speed signal is abnormal due to a wheel speed sensor malfunction, etc., assist may be limited.	-
	Batt Vol Keep	When insufficient auxiliary battery charge, or auxiliary battery degradation etc. causes the voltage to temporarily decrease, assist may be limited. After the auxiliary battery condition returns to normal, assist can be performed as usual.	-

Chassis > EMPS > Data List

Tester Display
Assist Limit Record 1

(b) Based on the "Assist Limit Record 1" information, the following Data List items and the information from the customer interview, explain the situation to the customer.

Chassis > EMPS > Data List

Tester Display
Record 1 Key Cycle
Record 1 Key Cycle Elapsed Time

HINT:

If it is necessary to investigate further into the past, check the "Assist Limit Record 2" and "Assist Limit Record 3" information in the same way as "Assist Limit Record 1".

END

Data List / Active Test

DATA LIST / ACTIVE TEST

DATA LIST

HINT:

Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

NOTICE:

In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.

(a) Turn the power switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / EMPS / Data List.

(f) Read the Data List according to the display on the Techstream.

Chassis > EMPS > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Meter Vehicle Velocity	Vehicle speed from speedometer	Min.: 0.0 km/h (0.0 MPH) Max.: 300.0 km/h (186.4 MPH)	0 km/h (0 MPH): Power switch on (READY) and vehicle stopped No significant fluctuation: Power switch on (READY) and vehicle driven at a constant speed	-
Wheel Speed Right	Rear right wheel speed	Min.: 0 km/h (0 MPH) Max.: 255 km/h (158 MPH)	0 km/h (0 MPH): Power switch on (READY) and vehicle stopped No significant fluctuation: Power switch on (READY) and vehicle driven at a constant speed	-
Wheel Speed Left	Rear left wheel speed	Min.: 0 km/h (0 MPH) Max.: 255 km/h (158 MPH)	0 km/h (0 MPH): Power switch on (READY) and vehicle stopped No significant fluctuation: Power switch on (READY) and vehicle driven at a constant speed	-
Motor Actual Current	Amount of current to motor	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort - The value increases when turning right and decreases when turning left	Power switch on (READY) and steering wheel being turned
Command Value Current	Requested current to motor	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort - The value increases when turning right and decreases when turning left	Power switch on (READY) and steering wheel being turned
Steering Angle Velocity	Steering angle speed	Min.: -32768 deg/s Max.: 32767 deg/s	Value changes in proportion to steering speed - The value increases when turning left and decreases when turning right	Power switch on (READY) and steering wheel being turned
Thermistor Temperature	ECU substrate temperature	Min.: -50.0°C (-58.0°F) Max.: 150.0°C (302.0°F)	-50°C to 150°C (-58°F to 302°F)	-
IG Power Supply	IG power source voltage	Min.: 0.0000 V Max.: 20.1531 V	8 to 16 V	Power switch on (IG)
Steering Angle Sens Sig	Steering sensor signal state	OK or NG(1) or NG(2) or NG(3)	OK: Steering sensor signal received NG(1): The learning has not completed NG(2): Steering sensor abnormal NG(3): Communication error	-
Steering Wheel Torque	Steering wheel torque	Min.: -327.68 Nm Max.: 7.00 Nm	Value changes in proportion to steering effort - The value increases when turning left and decreases when turning right	Power switch on (READY) and steering wheel being turned
Motor Rotation Angle	Motor rotation angle	Min.: 0.000 deg Max.: 1441.770 deg	During steering operation, motor rotation angle value changes from 0 to 360°	Power switch on (READY) and steering wheel being turned
Command Val Current 2	Requested current to motor	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor Voltage	Motor power supply voltage	Min.: 0.000 V Max.: 98.000 V	Approximately 27 V: Power switch on (READY) and steering wheel being turned Approximately 27 to 34 V: Power switch on (READY) and steering wheel not being turned	-
TRQ1 Zero Point Value	Zero point value of torque sensor 1	Min.: 0.0000 V Max.: 4.9725 V	2.3 to 2.7 V	Power switch on (READY) and steering wheel not being turned (without load)
TRQ2 Zero Point Value	Zero point value of torque sensor 2	Min.: 0.0000 V Max.: 4.9725 V	2.3 to 2.7 V	Power switch on (READY) and steering wheel not being turned (without load)
IG ON/OFF Times	Number of times of power switch turned on/off since latest DTC detection	Min.: 0 times Max.: 65535 times	-	-
Motor Overheat Record	Continuous overheat prevention control record	Unrec or Rec	Unrec	Unrec: Unrecorded Rec: Recorded The amount of power assist may be decreased to prevent the motor and ECUs from overheating if the steering wheel is continuously turned when the vehicle is either stopped or driven at a low speed, or if the steering wheel is kept in either full lock position for a long time.
Motor Lo Power Record	PIG power source voltage drop record	Unrec or Rec	Unrec	Unrec: Unrecorded Rec: Recorded If the PIG power source voltage decreases temporarily, the amount of power assist will be reduced.
Eng Rev Inter Record	Record of engine signal interruption	Unrec or Rec	Unrec	Unrec: Unrecorded Rec: Recorded
Str Angle Inter Record	Record of steering sensor signal interruption occurrence display	Unrec or Rec	Unrec	Unrec: Unrecorded Rec: Recorded
Spd Sig Invalid Record	Record of vehicle speed signal invalid	Unrec or Rec	Unrec	Unrec: Unrecorded Rec: Recorded
Battery Voltage Lo Record	Auxiliary battery voltage reduction history	Min.: 0 times Max.: 65535 times	0 to 65535 times	-
Battery Control Count (Body ECU)	Number of auxiliary battery load control operations	Min.: 0 times Max.: 65535 times	-	-
PS Assist Signal	Status of the record of power steering assist signal	OFF or ON	OFF: Power switch on (IG) ON: Power switch on (READY)	-
Ready Status	Ready status	OFF or Ready	OFF: Except power switch on (READY) Ready: Power switch on (READY)	-
Motor Actual Current 2	Amount of current to motor	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Rotation Angle Sens Avg(SIN)	Rotation angle sensor average (SIN)	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sens Avg(COS)	Rotation angle sensor average (COS)	Min.: 0.0000 V Max.: 4.9725 V	-	-
Motor Overheat Limit Cnt(Normal)	Number of times that assist limit was performed according to the estimated temperature of the motor coil and heat generating components of the power steering ECU assembly	Min.: 0 times Max.: 255 times	-	-
Assist Limit Cnt(Power Voltage Low)	Number of times that assist limit was performed due to auxiliary battery voltage having dropped to 9 V or below	Min.: 0 times Max.: 255 times	-	-
Power Vol Low Prevention Limit Cnt	Number of times that assist limit was performed due to auxiliary battery voltage having dropped to 9.7 V or below	Min.: 0 times Max.: 255 times	-	-
Eng Stall/Ready OFF Cnt	Number of times that assist limit was performed after the engine stalled and the power switch was turned off	Min.: 0 times Max.: 255 times	-	-
Motor Overheat Limit Cnt(Motor Overload)	Number of times that assist limit was performed to prevent the system from overheating when the motor was overloaded due to the steering wheel being turned to the full lock position or a tire hitting a curb	Min.: 0 times Max.: 255 times	-	-
Assist Limit Cnt(Vehicle Spd Sig Malf)	Number of times that assist power was set to a value suitable for high-speed driving when high speed is detected due to an abnormal vehicle speed signal	Min.: 0 times Max.: 255 times	-	-
Battery Voltage Keep Limit Cnt	Number of times that the system was limited to conserve auxiliary battery voltage	Min.: 0 times Max.: 255 times	-	-
Assist Limit Record 1	Information of assist limit that was used in the past or is currently in use (latest history)	Unrec, Mtr Overheat, Pow Vol Low, Pow Vol Low Prevent, Eng Stall, Ready OFF, Mtr Overload, Vhcl Spd Sig Malf, Batt Vol Keep	-	-
Record 1 Key Cycle	Number of times that the power switch was turned on (IG) before Assist Limit Record 1 was stored	Min.: 0 times Max.: 65535 times	-	-
Record 1 Key Cycle Elapsed Time	Period of time that elapsed since the power switch was turned on (IG) before Assist Limit Record 1 was stored	Min.: 0.0 s Max.: 53687091.1 s	-	-
Record 1 Power Source	Power source operating status when Assist Limit Record 1 was stored	No Data, Running, Stop	-	-
Assist Limit Record 2	Information of assist limit that was used in the past (second latest history)	Unrec, Mtr Overheat, Pow Vol Low, Pow Vol Low Prevent, Eng Stall, Ready OFF, Mtr Overload, Vhcl Spd Sig Malf, Batt Vol Keep	-	-
Record 2 Key Cycle	Number of times that the power switch was turned on (IG) after Assist Limit Record 2 was stored before Assist Limit Record 1 was stored	Min.: 0 times Max.: 65535 times	-	-
Record 2 Key Cycle Elapsed Time	Period of time that elapsed since the power switch was turned on (IG) before Assist Limit Record 2 was stored	Min.: 0.0 s Max.: 53687091.1 s	-	-
Record 2 Power Source	Power source operating status when Assist Limit Record 2 was stored	No Data, Running, Stop	-	-
Assist Limit Record 3	Information of assist limit that was used in the past (third latest history)	Unrec, Mtr Overheat, Pow Vol Low, Pow Vol Low Prevent, Eng Stall, Ready OFF, Mtr Overload, Vhcl Spd Sig Malf, Batt Vol Keep	-	-
Record 3 Key Cycle	Number of times that the power switch was turned on (IG) after Assist Limit Record 3 was stored before Assist Limit Record 2 was stored	Min.: 0 times Max.: 65535 times	-	-
Record 3 Key Cycle Elapsed Time	Period of time that elapsed since the power switch was turned on (IG) before Assist Limit Record 3 was stored	Min.: 0.0 s Max.: 53687091.1 s	-	-
Record 3 Power Source	Power source operating status when Assist Limit Record 3 was stored	No Data, Running, Stop	-	-
Current Key Cycle	Number of times that power switch was turned on (IG)	Min.: 0 times Max.: 65535 times	-	-
Current Key Cycle Elapsed Time	Time elapsed since power switch was turned on (IG)	Min.: 0.0 s Max.: 53687091.1 s	-	-
Steering Angle	Steering angle	Min.: -3072.0 deg Max.: 3070.5 deg	-	-
Torque Sensor 1 Output	Torque sensor 1 output value	Min.: 0.0000 V Max.: 4.9725 V	-	-
Torque Sensor 2 Output	Torque sensor 2 output value	Min.: 0.0000 V Max.: 4.9725 V	-	-
Torque Sensor 1 Power Supply	Torque sensor 1 power supply voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Torque Sensor 2 Power Supply	Torque sensor 2 power supply voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sensor Output 1	Rotation angle sensor Vx1 output voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sensor Output 2	Rotation angle sensor Vx2 output voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sensor Output 3	Rotation angle sensor Vy1 output voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sensor Output 4	Rotation angle sensor Vy2 output voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Motor 1 Terminal Current (U)	Motor 1 terminal current (U phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 1 Terminal Current (V)	Motor 1 terminal current (V phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 1 Terminal Current (W)	Motor 1 terminal current (W phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Current (U)	Motor 2 terminal current (U phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Current (V)	Motor 2 terminal current (V phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Current (W)	Motor 2 terminal current (W phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 1 U Phase Duty	Motor 1 U phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 1 V Phase Duty	Motor 1 V phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 1 W Phase Duty	Motor 1 W phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 2 U Phase Duty	Motor 2 U phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 2 V Phase Duty	Motor 2 V phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 2 W Phase Duty	Motor 2 W phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 1 Terminal Volt (U)	Motor 1 terminal voltage (U phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 1 Terminal Volt (V)	Motor 1 terminal voltage (V phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 1 Terminal Volt (W)	Motor 1 terminal voltage (W phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Volt (U)	Motor 2 terminal voltage (U phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Volt (V)	Motor 2 terminal voltage (V phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Volt (W)	Motor 2 terminal voltage (W phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 1 PIG Power Supply	Power supply voltage to active motor 1	Min.: 0.0000 V Max.: 20.1531 V	9 to 16 V	Power switch on (READY) and steering wheel being turned
Motor 2 PIG Power Supply	Power supply voltage to active motor 2	Min.: 0.0000 V Max.: 20.1531 V	9 to 16 V	Power switch on (READY) and steering wheel being turned
The Number of DTCs	Number of detected DTCs when freeze frame data was stored	Min.: 0 Max.: 255	0 to 255	-

HINT:

With the vehicle stopped or driving very slowly, if the steering wheel is turned repeatedly or turned to a lock position and the vehicle is driven for an extended period of time, the amount of power assist is decreased to prevent overheating of the motor and ECU. If this occurs, power switch on (READY) and do not turn the steering wheel for approximately 10 minutes to improve power assist.
If the auxiliary battery is not sufficiently charged or the voltage decreases temporarily, the amount of power assist is reduced and the EPS warning light comes on. In such cases, the amount of power assist returns to normal when the auxiliary battery voltage recovers.

Diagnosis System

DIAGNOSIS SYSTEM

CHECK DLC3

(a) Check the DLC3.

Click here

CHECK WARNING LIGHT

(a) When a problem occurs in the power steering system, the EPS warning light in the combination meter assembly comes on to inform the driver of the problem.

*a	EPS Warning Light

Diagnostic Trouble Code Chart

DIAGNOSTIC TROUBLE CODE CHART

Power Steering System

DTC No.	Detection Item	DTC Detection Condition	Warning Indicate	Return-to-normal Condition	Note
C1511	Torque Sensor1	Torque sensor malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1512	Torque Sensor2	Torque sensor malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1513	Torque Sensor Deviation Excessive	Torque sensor malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1514	Torque Sensor Power Supply Voltage	Torque sensor malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1515	Torque Sensor Zero Point Adjustment Undone	This DTC is stored when torque sensor zero point calibration has not been performed.	EPS warning light: Comes on	Zero point calibration is performed or the power switch is turned on (IG) again	There is no malfunction if this DTC is not output again after performing zero point calibration.
C1516	Torque Sensor Zero Point Adjustment Incomplete	Torque sensor zero point calibration is incomplete due to the steering wheel being touched during calibration.	EPS warning light: Comes on	The DTC is cleared	There is no malfunction if this DTC is not output again after clearing the DTC and torque sensor calibration value, and performing zero point calibration.
C1517	Torque Hold	Torque sensor malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1521	Short in Motor Circuit	Motor overcurrent	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1522	Power Supply Sensor	Motor current sensor malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1523	Current Deviation Excessive	Excessively large current deviation	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1528	Motor Rotation Angle Sensor	Motor rotation angle sensor malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1531	ECU Malfunction	ECU internal malfunction (CPU malfunction)	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1532	ECU Malfunction	ECU internal malfunction (Peripheral circuit malfunction)	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1533	Temperature Sensor Circuit is Low or High	ECU internal malfunction (Substrate temperature sensor malfunction)	EPS warning light: Comes on	The ECU judges the system has returned to normal	-
C1534	EEPROM	ECU internal malfunction (EEPROM error)	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1541	Vehicle Speed Signal	A vehicle speed signal malfunction is detected	EPS warning light: Comes on	The ECU judges the system has returned to normal	-
C1551	IG Power Supply Voltage	When the PIG power supply voltage is normal, the IG power supply voltage is 18.5 V or higher	EPS warning light: Comes on	The ECU judges the system has returned to normal	-
C1552	PIG Power Supply Voltage	PIG power source circuit malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1554	Power Supply Relay Failure	Power source relay circuit malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1555	Motor Relay Welding Failure	Motor relay circuit malfunction	EPS warning light: Comes on	Power switch is turned on (IG) again	-
C1567	Error in Matching of ECUs	An incompatible hybrid vehicle control ECU is detected An incompatible main body ECU (multiplex network body ECU) is detected An incompatible skid control ECU (brake booster with master cylinder assembly) is detected	EPS warning light: Comes on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-
C1581	Assist Map Number Un-Writing	Assist map not written in power steering ECU (rack and pinion power steering gear assembly)	EPS warning light: Comes on	Assist Map Writing is performed or the power switch is turned on (IG) again	-
C1582	Assist Map Number Mismatch	Assist map number mismatch	EPS warning light: Does not come on	Assist Map Writing is performed or the power switch is turned on (IG) again	-
U0126	Lost Communication With Steering Angle Sensor Module	Lost communication with steering angle sensor	EPS warning light: Comes on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-
U0129	Lost Communication with Brake System Control Module	Lost communication with skid control ECU (Brake booster with master cylinder assembly)	EPS warning light: Comes on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-
U023A	Lost Communication with Front Camera Module	Lost communication with forward recognition camera	EPS warning light: Does not come on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-
U0293	Lost Communication with Hybrid Control Module	Lost communication with hybrid vehicle control ECU	EPS warning light: Does not come on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-

Dtc Check / Clear

DTC CHECK / CLEAR

CHECK DTCs (USING TECHSTREAM)

(a) Turn the power switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / EMPS / Trouble Codes.

Chassis > EMPS > Trouble Codes

(f) Check the details of the DTCs.

Click here

CHECK DTCs (USING SST CHECK WIRE)

(a) Using SST, connect terminals 13 (TC) and 4 (CG) of the DLC3.

SST: 09843-18040

DLC3

(b) Turn the power switch on (IG).

(c) Read and write down any DTCs indicated by the blinking of the EPS warning light in the combination meter assembly. Refer to the illustration to the right for examples of the normal system code and DTCs 21 and 22.

*a	Normal System Code
*b	Codes 21 and 22
*c	ON
*d	OFF
*e	Seconds
*f	Code 21
*g	Code 22

HINT:

If the EPS warning light does not blink to display stored DTCs or the normal system code, inspect the circuit shown in the table below.

Trouble Area

Link

EPS warning light circuit
If two or more malfunctions are detected simultaneously, DTCs will be displayed in ascending numerical order.

(d) Refer to Diagnostic Trouble Code Chart for DTC information.

Click here

(e) Check the details of the DTCs.

EPS DTC

EPS Warning Light Display	Tester Display
11	C1511
	C1512
	C1513
	C1514
	C1517
12	C1528
13	C1541
15	C1515
16	C1516
22	C1552
23	C1554
24	C1521
	C1522
	C1523
25	C1531
	C1532
	C1533
	C1534
	C1551
	C1555
26	C1581
26	C1582
41	U0100
42	U0129
44	C1567
45	U023A
47	U0126

CLEAR DTCs (USING TECHSTREAM)

(a) Turn the power switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / EMPS / Trouble Codes.

Chassis > EMPS > Trouble Codes

(f) Clear the DTCs.

Chassis > EMPS > Clear DTCs

(g) Turn the power switch off.

(h) Disconnect the Techstream from the DLC3.

EPS Warning Light Circuit

CAUTION / NOTICE / HINT

NOTICE:

Perform this troubleshooting procedure when no DTCs are output, including DTCs related to CAN communication system malfunctions.
If the customer reports that the steering feels heavy, refer to the "Heavy steering" item in the Problem Symptoms Table.
Click here

PROCEDURE

1.	INSPECT COMBINATION METER ASSEMBLY

(a) Perform the Active Test of the combination meter assembly using the Techstream.

Click here

Body Electrical > Combination Meter > Active Test

Tester Display
EPS Warning

(b) Check the combination meter assembly.

OK:

The EPS warning light turns on or off in accordance with the Techstream operation.

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY

GO TO METER / GAUGE SYSTEM

Fail-safe Chart

FAIL-SAFE CHART

If a problem occurs in the power steering system, the power steering assist will be stopped or the amount of power assist will be decreased to protect the system.

Power Steering System

Malfunction	Fail-safe Operation	EPS warning light	Buzzer
Torque sensor (rack and pinion power steering gear assembly) malfunction Power steering motor (rack and pinion power steering gear assembly) malfunction Power steering ECU (rack and pinion power steering gear assembly) malfunction	Power steering assist stops or assist amount is limited	Red or yellow	Sounds intermittently or once
Vehicle speed signal malfunction Skid control ECU (brake booster with master cylinder assembly) malfunction History of power steering ECU (rack and pinion power steering gear assembly) overheating History of decrease in battery voltage (not malfunction)	Power steering assist is temporarily limited	Yellow	Sounds once

HINT:

If the power steering assist stops, the EPS warning light comes on (red).
If the amount of power assist is reduced, the EPS warning light comes on (yellow) and a vibration or sound may occur.
The amount of power assist may be decreased to prevent the motor and ECUs from overheating if the steering wheel is continuously turned when the vehicle is either stopped or driven at a low speed, or if the steering wheel is kept at either full lock position for a long time. In such cases, the amount of power assist returns to normal if the steering wheel is not turned for approximately 10 minutes with the power switch on (READY).
If the auxiliary battery is not sufficiently charged or the voltage decreases temporarily, the amount of power assist will be reduced and the EPS warning light will come on. In such cases, the amount of power assist returns to normal when the auxiliary battery voltage recovers.

Freeze Frame Data

FREEZE FRAME DATA

FREEZE FRAME DATA

NOTICE:

It is difficult to show the specified values (judgment values) clearly because freeze frame data values change significantly due to differences in measurement conditions, surroundings, or vehicle conditions. For this reason, there may be a problem even when the values are within specification.
Turn the power switch on (IG) and park the vehicle on level ground. Check the freeze frame data by using the Techstream.

(a) Turn the power switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Check the freeze frame data on the Techstream.

Chassis > EMPS

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Meter Vehicle Velocity	Vehicle speed from speedometer	Min.: 0.0 km/h (0.0 MPH) Max.: 300.0 km/h (186.4 MPH)	0 km/h (0 MPH): Power switch on (READY) and vehicle stopped No significant fluctuation: Power switch on (READY) and vehicle driven at a constant speed	-
Wheel Speed Right	Rear right wheel speed	Min.: 0 km/h (0 MPH) Max.: 255 km/h (158 MPH)	0 km/h (0 MPH): Power switch on (READY) and vehicle stopped No significant fluctuation: Power switch on (READY) and vehicle driven at a constant speed	-
Wheel Speed Left	Rear left wheel speed	Min.: 0 km/h (0 MPH) Max.: 255 km/h (158 MPH)	0 km/h (0 MPH): Power switch on (READY) and vehicle stopped No significant fluctuation: Power switch on (READY) and vehicle driven at a constant speed	-
Motor Actual Current	Amount of current to motor	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort - The value increases when turning right and decreases when turning left	Power switch on (READY) and steering wheel being turned
Command Value Current	Requested current to motor	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort - The value increases when turning right and decreases when turning left	Power switch on (READY) and steering wheel being turned
Steering Angle Velocity	Steering angle speed	Min.: -32768 deg/s Max.: 32767 deg/s	Value changes in proportion to steering speed - The value increases when turning left and decreases when turning right	Power switch on (READY) and steering wheel being turned
Thermistor Temperature	ECU substrate temperature	Min.: -50.0°C (-58.0°F) Max.: 150.0°C (302.0°F)	-50°C to 150°C (-58°F to 302°F)	-
IG Power Supply	IG power source voltage	Min.: 0.0000 V Max.: 20.1531 V	8 to 16 V	Power switch on (IG)
Steering Wheel Torque	Steering wheel torque	Min.: -327.68 Nm Max.: 7.00 Nm	Value changes in proportion to steering effort - The value increases when turning left and decreases when turning right	Power switch on (READY) and steering wheel being turned
Motor Rotation Angle	Motor rotation angle	Min.: 0.000 deg Max.: 1441.770 deg	During steering operation, motor rotation angle value changes from 0 to 360°	Power switch on (READY) and steering wheel being turned
Command Val Current 2	Requested current to motor	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor Voltage	Motor power supply voltage	Min.: 0.000 V Max.: 98.000 V	Approximately 27 V: Power switch on (READY) and steering wheel being turned Approximately 27 to 34 V: Power switch on (READY) and steering wheel not being turned	-
TRQ1 Zero Point Value	Zero point value of torque sensor 1	Min.: 0.0000 V Max.: 4.9725 V	2.3 to 2.7 V	Power switch on (READY) and steering wheel not being turned (without load)
TRQ2 Zero Point Value	Zero point value of torque sensor 2	Min.: 0.0000 V Max.: 4.9725 V	2.3 to 2.7 V	Power switch on (READY) and steering wheel not being turned (without load)
PS Assist Signal	Status of the record of power steering assist signal	OFF or ON	OFF: Power switch on (IG) ON: Power switch on (READY)	-
Ready Status	Ready status	OFF or Ready	OFF: Except power switch on (READY) Ready: Power switch on (READY)	-
Motor Actual Current 2	Amount of current to motor	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Rotation Angle Sens Avg(SIN)	Rotation angle sensor average (SIN)	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sens Avg(COS)	Rotation angle sensor average (COS)	Min.: 0.0000 V Max.: 4.9725 V	-	-
Steering Angle	Steering angle	Min.: -3072.0 deg Max.: 3070.5 deg	-	-
Torque Sensor 1 Output	Torque sensor 1 output value	Min.: 0.0000 V Max.: 4.9725 V	-	-
Torque Sensor 2 Output	Torque sensor 2 output value	Min.: 0.0000 V Max.: 4.9725 V	-	-
Torque Sensor 1 Power Supply	Torque sensor 1 power supply voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Torque Sensor 2 Power Supply	Torque sensor 2 power supply voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sensor Output 1	Rotation angle sensor Vx1 output voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sensor Output 2	Rotation angle sensor Vx2 output voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sensor Output 3	Rotation angle sensor Vy1 output voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Rotation Angle Sensor Output 4	Rotation angle sensor Vy2 output voltage	Min.: 0.0000 V Max.: 4.9725 V	-	-
Motor 1 Terminal Current (U)	Motor 1 terminal current (U phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 1 Terminal Current (V)	Motor 1 terminal current (V phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 1 Terminal Current (W)	Motor 1 terminal current (W phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Current (U)	Motor 2 terminal current (U phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Current (V)	Motor 2 terminal current (V phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Current (W)	Motor 2 terminal current (W phase)	Min.: -327.68 A Max.: 327.67 A	Value changes in proportion to steering effort	Power switch on (READY) and steering wheel being turned
Motor 1 U Phase Duty	Motor 1 U phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 1 V Phase Duty	Motor 1 V phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 1 W Phase Duty	Motor 1 W phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 2 U Phase Duty	Motor 2 U phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 2 V Phase Duty	Motor 2 V phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 2 W Phase Duty	Motor 2 W phase duty	Min.: 0.00% Max.: 100.00%	-	-
Motor 1 Terminal Volt (U)	Motor 1 terminal voltage (U phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 1 Terminal Volt (V)	Motor 1 terminal voltage (V phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 1 Terminal Volt (W)	Motor 1 terminal voltage (W phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Volt (U)	Motor 2 terminal voltage (U phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Volt (V)	Motor 2 terminal voltage (V phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 2 Terminal Volt (W)	Motor 2 terminal voltage (W phase)	Min.: 0.000 V Max.: 98.000 V	Value changes within 4 to 35 V range	Power switch on (READY) and steering wheel being turned
Motor 1 PIG Power Supply	Power supply voltage to active motor 1	Min.: 0.0000 V Max.: 20.1531 V	9 to 16 V	Power switch on (READY) and steering wheel being turned
Motor 2 PIG Power Supply	Power supply voltage to active motor 2	Min.: 0.0000 V Max.: 20.1531 V	9 to 16 V	Power switch on (READY) and steering wheel being turned

How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

Use the following procedure to troubleshoot the power steering system.
*: Use the Techstream.

PROCEDURE

1.	VEHICLE BROUGHT TO WORKSHOP

2.	INSPECT AUXILIARY BATTERY

(a) Turn the power switch off.

(b) Measure the voltage of the auxiliary battery.

Standard Voltage:

11 to 14 V

HINT:

If the voltage is below 11 V, recharge or replace the auxiliary battery before proceeding to the next step.

3.	CHECK DTC AND FREEZE FRAME DATA*

HINT:

Refer to DTC Check / Clear.

Chassis > EMPS > Trouble Codes

4.	PROBLEM SYMPTOM CONFIRMATION

Result	Proceed to
Symptom does not occur.	A
Symptom occurs.	B

GO TO STEP 6

5.	SYMPTOM SIMULATION

6.	CHECK CAN COMMUNICATION SYSTEM*

(a) Check for DTCs.

Click here

Result	Proceed to
CAN communication system DTCs are not output.	A
CAN communication system DTCs are output.	B

HINT:

If any CAN communication system DTCs are output, perform troubleshooting for the CAN communication system first.
If communication to the rack and pinion power steering gear assembly cannot be established through the Techstream, inspect terminals CANH and CANL of the DLC3 and the rack and pinion power steering gear assembly, and the IG circuit of the rack and pinion power steering gear assembly.

PROCEED TO CAN COMMUNICATION SYSTEM

7.	CHECK FOR DTC*

(a) Check for DTCs.

Chassis > EMPS > Trouble Codes

HINT:

Refer to Diagnostic Trouble Code Chart when any DTCs are output.

Click here

Result	Proceed to
DTCs are not output.	A
DTCs are output.	B

GO TO STEP 10

8.	PROBLEM SYMPTOMS TABLE

(a) Refer to Problem Symptoms Table.

Click here

Result	Proceed to
Fault is not listed in Problem Symptoms Table.	A
Fault is listed in Problem Symptoms Table.	B

GO TO STEP 10

9.	OVERALL ANALYSIS AND TROUBLESHOOTING*

(a) Refer to Terminals of ECU.

Click here

(b) Refer to Data List / Active Test.

Click here

10.	REPAIR OR REPLACE

11.	CONFIRMATION TEST

END

On-vehicle Inspection

ON-VEHICLE INSPECTION

PROCEDURE

1. CHECK STEERING EFFORT (TORQUE)

NOTICE:

These service operations may affect the SRS airbags. Be sure to read the precautionary notices concerning the SRS airbag system before servicing.

Click here

(a) Stop the vehicle on a level, paved surface and align the wheels straight ahead.

(b) Remove the horn button assembly.

Click here

(d) Using a torque wrench, check that the steering wheel set bolt is properly tightened.

Torque:

62 N·m {632 kgf·cm, 46 ft·lbf}

(e) Turn the power switch on (READY) so that the power steering is ready to operate.

(f) Turn the steering wheel 90 degrees to the right and check steering effort (torque) with the steering wheel turned. Check in the opposite direction using the same method.

Standard Steering Effort (Reference):

5.5 N*m (56 kgf*cm, 49 in.*lbf) or less

(g) Align the front wheels facing straight ahead.

(h) Turn the power switch off.

(i) Disconnect the cable from the negative (-) auxiliary battery terminal.

NOTICE:

When disconnecting the cable, some systems need to be initialized after the cable is reconnected.

Click here

(j) Install the horn button assembly.

Click here

Parts Location

PARTS LOCATION

ILLUSTRATION

*1	FORWARD RECOGNITION CAMERA	*2	BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - SKID CONTROL ECU
*3	RACK AND PINION POWER STEERING GEAR ASSEMBLY - POWER STEERING ECU -POWER STEERING MOTOR -TORQUE SENSOR	*4	NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY - EPS FUSE
*5	COMBINATION METER ASSEMBLY	*6	HYBRID VEHICLE CONTROL ECU
*7	MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)	*8	INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - IG1-NO. 1 RELAY - EPS-IG1 FUSE
*9	DLC3	*10	AIR CONDITIONING AMPLIFIER ASSEMBLY
*11	STEERING SENSOR	-	-

Precaution

PRECAUTION

PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE AUXILIARY BATTERY TERMINAL

NOTICE:

When disconnecting the cable from the negative (-) auxiliary battery terminal, initialize the following system(s) after the cable is reconnected.

System	Procedure
Lane Departure Alert System (w/ Steering Control)
Pre-collision System
Intelligent Clearance Sonar System
Lighting System (for HV Model with Cornering Light)
Parking Assist Monitor System
Panoramic View Monitor System

HANDLING PRECAUTIONS FOR SRS AIRBAG SYSTEM

(a) This vehicle is equipped with a Supplemental Restraint System (SRS). Failure to carry out service operations in the correct sequence could cause the SRS to unexpectedly deploy during servicing. This may cause a serious accident.

Before servicing (including inspection, replacement, removal and installation of parts), be sure to read the precautionary notices for the Supplemental Restraint System.

Click here

PRECAUTIONS FOR REMOVAL, INSTALLATION AND REPLACEMENT OF ELECTRONIC POWER STEERING COMPONENTS

(a) Be sure to align the front wheels straight ahead when removing and installing the rack and pinion power steering gear assembly.

(b) When disconnecting the steering intermediate shaft assembly, be sure to place matchmarks before starting the operation.

Click here

HANDLING PRECAUTION

(a) When handling electronic parts:

(1) Do not subject any parts such as ECUs and relays to any impact. Replace them with new ones if dropped or subjected to a strong impact.

(2) Do not expose any electronic parts to high temperatures or humidity.

(3) In order to prevent deformation or malfunctions due to static electricity, do not touch the connector terminals.

(b) When handling the rack and pinion power steering gear assembly:

(1) When replacing the power steering ECU (rack and pinion power steering gear assembly), make sure to replace each rack and pinion power steering gear assembly with a new one.

NOTICE:

Do not use a rack and pinion power steering gear assembly intended from another vehicle (demo models, etc.).

(2) Do not subject the rack and pinion power steering gear assembly to any strong impact (particularly the motor and torque sensor). Replace these parts with new ones if dropped or subjected to any severe impact.

(3) Do not pull the harness when carrying the rack and pinion power steering gear assembly.

(4) When the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here

PRECAUTIONS FOR CAN COMMUNICATION

(a) CAN communication lines are used to receive information from the skid control ECU (brake booster with master cylinder assembly) and ECM and to transmit warnings to the combination meter assembly. When problems are detected in the CAN communication lines, CAN communication DTCs are stored.

(b) If any CAN communication system DTCs are output, perform troubleshooting for the CAN communication system first.

(c) The wiring used for each communication line is a twisted pair of wires that have an equal length. Do not temporarily repair a CAN communication line with a bypass wire or equivalent.

Problem Symptoms Table

PROBLEM SYMPTOMS TABLE

HINT:

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table.
Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
Inspect the fuses and relays related to this system before inspecting the suspected areas below.

Power Steering System

Symptom	Suspected Area	Link
Heavy steering	Check assist limit record
	Front tires (improperly inflated, unevenly worn)
	Front wheel alignment (incorrect)
	Front suspension (Lower ball joint)
	Rack and pinion power steering gear assembly
Steering effort differs between right and left or is uneven	Rotation angle sensor initialization and torque sensor zero point calibration incomplete
	Front tires (improperly inflated, unevenly worn)
	Front wheel alignment (incorrect)
	Front suspension (Lower ball joint)
	Rack and pinion power steering gear assembly
	Steering column assembly (for Manual Tilt and Manual Telescopic Steering Column)
	Steering column assembly (for Power Tilt and Power Telescopic Steering Column)
While driving, steering effort does not change in accordance with vehicle speed, or steering wheel does not return to its centered position easily	Skid control ECU (Brake Booster with Master Cylinder Assembly)
	Speed sensor
	Rack and pinion power steering gear assembly
	CAN communication system
Friction sounds occur when turning steering wheel during low speed driving	Rack and pinion power steering gear assembly
	Steering column assembly (for Manual Tilt and Manual Telescopic Steering Column)
	Steering column assembly (for Power Tilt and Power Telescopic Steering Column)
	Spiral with cable sensor sub-assembly
	Steering column cover contacting steering wheel assembly (for Manual Tilt and Manual Telescopic Steering Column)
	Steering column cover contacting steering wheel assembly (for Power Tilt and Power Telescopic Steering Column)
High-pitched sound (squeaking) occurs when turning steering wheel slowly with vehicle stopped	Rack and pinion power steering gear assembly
	Steering wheel installation (incorrect)
Steering wheel vibrates and noise occurs when turning steering wheel from lock to lock	Rack and pinion power steering gear assembly
	Steering column assembly (for Manual Tilt and Manual Telescopic Steering Column)
	Steering column assembly (for Power Tilt and Power Telescopic Steering Column)
	Steering wheel installation (incorrect)
EPS warning light remains on	EPS warning light circuit

System Description

SYSTEM DESCRIPTION

DESCRIPTION

(a) The power steering ECU (rack and pinion power steering gear assembly) generates the necessary steering assist torque by calculating the steering assist force and controlling the motor current, based on the steering torque information from the torque sensor (rack and pinion power steering gear assembly), vehicle speed information from the skid control ECU (brake booster with master cylinder assembly), and information from the ECUs.

(b) When there is a drop in the power source voltage, the rear window defogger, windshield deicer, outer mirror heater, PTC heater and seat heater operations are limited as part of power steering system load control.

(c) When there is a drop in the power source that may require an increase in steering force, the system illuminates the power steering warning light in order to warn the driver.

Function of Components:

Component		Function
Rack and Pinion Power Steering Gear Assembly HINT: The components listed on the right are built-in	Power Steering ECU	Calculates the motor operation current based on the steering torque and vehicle speed signals, and outputs it to the motor. When a malfunction is detected in the power steering system, it outputs a warning signal to the combination meter assembly.
	Power Steering Motor	Generates power assist in accordance with the actuation current received from the power steering ECU. The built-in motor rotation angle sensor detects the rotation angle of the motor.
	Torque Sensor	Detects the steering torque.
	Reduction Mechanism	Decelerates the motor rotation torque and transmits it to the rack shaft.
Steering Sensor		Detects the steering angle and steering direction.
Skid Control ECU (Brake Booster with Master Cylinder Assembly)		Sends the vehicle speed signal and steering coordinated control amount signal to the rack and pinion power steering gear assembly.
Hybrid Vehicle Control ECU		Transmits the READY signal to the power steering ECU (rack and pinion power steering gear assembly).
Air Conditioning Amplifier Assembly		Receives a signal from the power steering ECU (rack and pinion power steering gear assembly) to limit electrical usage.
Combination Meter Assembly	EPS Warning Light	Illuminates to alert the driver when the power steering ECU (rack and pinion power steering gear assembly) detects a malfunction in the power steering system.
	Multi-information Display	Displays a warning message to inform the driver of a malfunction in the system.
	Master Warning Light	Illuminates when a warning message is displayed on the multi-information display.
	Multi Buzzer	Sounds to warn the driver of a malfunction in the system.
Forward Recognition Camera		Requests steering assist torque when the lane departure alert system judges that the vehicle is departing from its lane.

System Diagram

SYSTEM DIAGRAM

Terminals Of Ecu

TERMINALS OF ECU

TERMINALS OF ECU

Component without harness connected

(Rack and Pinion Power Steering Gear Assembly)

HINT:

The rack and pinion power steering gear assembly uses waterproof connectors. Therefore, voltage or waveforms cannot be checked with the connectors connected to the vehicle.
Use the Data List and Active Test on the Techstream to check the operation of the rack and pinion power steering gear assembly and check that communication is established.
Click here

Terminal No. (Symbol)	Terminal Description
C67-4 (IG)	IG power source
C67-7 (PGND)	power ground
C67-8 (PIG)	power source
C67-10 (CANH)	CAN communication line
C67-11 (CANL)	CAN communication line

CHECK WIRE HARNESS SIDE CONNECTOR

Front view of wire harness connector

(to Rack and Pinion Power Steering Gear Assembly)

(a) Disconnect the C67 rack and pinion power steering gear assembly.

(b) Measure the voltage and resistance according to the value(s) in the table below.

Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
C67-4 (IG) - Body ground	W - Body ground	IG power source	Power switch on (IG)	8 to 16 V
C67-7 (PGND) - Body ground	B - Body ground	power ground	Always	Below 1 Ω
C67-8 (PIG) - Body ground	W - Body ground	power source	Always	9 to 16 V

Lost Communication With Steering Angle Sensor Module (U0126,U0129,U023A,U0293)

DESCRIPTION

The power steering ECU (rack and pinion power steering gear assembly) receives signals from the hybrid vehicle control ECU, steering sensor, skid control ECU (brake booster with master cylinder assembly) and forward recognition camera via CAN communication.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
U0126	Lost Communication With Steering Angle Sensor Module	Lost communication with steering angle sensor	CAN communication system Steering angle sensor Rack and pinion power steering gear assembly	EPS warning light: Comes on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-
U0129	Lost Communication with Brake System Control Module	Lost communication with skid control ECU (Brake booster with master cylinder assembly)	CAN communication system Skid control ECU (Brake booster with master cylinder assembly) Rack and pinion power steering gear assembly	EPS warning light: Comes on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-
U023A	Lost Communication with Front Camera Module	Lost communication with forward recognition camera	CAN communication system Forward recognition camera Rack and pinion power steering gear assembly	EPS warning light: Does not come on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-
U0293	Lost Communication with Hybrid Control Module	Lost communication with hybrid vehicle control ECU	CAN communication system Hybrid vehicle control ECU	EPS warning light: Does not come on	The ECU judges the system has returned to normal or the power switch is turned on (IG) again	-

PROCEDURE

1.	GO TO CAN COMMUNICATION SYSTEM

(a) Go to CAN communication system.

Click here

END

Power Steering System(for Gasoline Model)

Heated Steering Wheel System(for Gasoline Model)

See More:

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