Toyota Yaris: Power Steering System / Power Steering Torque Sensor "B" Supply Voltage Circuit Voltage Above Threshold (C151B17)

Toyota Yaris XP210 (2020-2025) Reapir and Service Manual / Steering / Power Assist Systems / Power Steering System / Power Steering Torque Sensor "B" Supply Voltage Circuit Voltage Above Threshold (C151B17)

DESCRIPTION

The power steering ECU assembly supplies a voltage of 5 V to the torque sensor (electric power steering column sub-assembly) and monitors the voltage value of the Hall IC inside the torque sensor (electric power steering column sub-assembly) which changes in response to changes in the magnetic flux density (steering torque) detected by the Hall IC, and calculates the assist torque.

While DTC C151B17 is detected, power assist is stopped or assist amount is limited due to fail-safe operation.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Return-to-normal Condition	Note
C151B17	Power Steering Torque Sensor "B" Supply Voltage Circuit Voltage Above Threshold	TRQV2 voltage is 5.6 V or more	Torque sensor (Electric power steering column sub-assembly) Power steering ECU assembly	EPS warning light: Comes on	Ignition switch ON again	-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When the electric power steering column sub-assembly has been replaced, perform Power Steering ECU Initial Setting (assist map writing).
Click here
When the power steering ECU assembly has been replaced, perform Power Steering ECU Initial Setting (assist map writing).
Click here

PROCEDURE

1.	INSPECT TORQUE SENSOR (ELECTRIC POWER STEERING COLUMN SUB-ASSEMBLY) (CHECK FOR SHORT)

(a) Disconnect the z7 power steering ECU assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
z7-3 (TRQV2) - Body ground	Always	10 kΩ or higher
z7-3 (TRQV2) - z7-2 (TRQG2)	Always	10 kΩ or higher

REPLACE ELECTRIC POWER STEERING COLUMN SUB-ASSEMBLY

2.	INSPECT POWER STEERING ECU ASSEMBLY (POWER SOURCE OF TORQUE SENSOR)

(a) Start the engine.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
z7-3 (TRQV2) - z7-2 (TRQG2)	Engine running	4.5 to 5.5 V

*a	Component with harness connected (Power Steering ECU Assembly)

REPLACE ELECTRIC POWER STEERING COLUMN SUB-ASSEMBLY

REPLACE POWER STEERING ECU ASSEMBLY

Power Steering Torque Sensor "A" Supply Voltage Circuit Voltage Above Threshold (C151A17)

DESCRIPTION The power steering ECU assembly supplies a voltage of 5 V to the torque sensor (electric power steering column sub-assembly) and monitors the voltage value of the Hall IC inside the torque sensor (electric power steering column sub-assembly) which changes in response to changes in the magnetic flux density (steering torque) detected by the Hall IC, and calculates the assist torque...

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