Toyota Yaris: Power Steering System / Problem Symptoms Table

Toyota Yaris XP210 (2020-2026) Reapir and Service Manual / Steering / Power Assist Systems / Power Steering System / 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	Front tires (improperly inflated, unevenly worn)
	Front wheel alignment (incorrect)
	Front suspension (Lower ball joint)
	Steering gear assembly
	Auxiliary battery and power source circuit
	Power source voltage of power steering ECU assembly
	Power steering ECU assembly
	Vehicle condition (Steering wheel is turned from left to right repeatedly with vehicle stopped or heavy load is continuously applied to vehicle)
Heavy Steering (EPS Warning Light (Yellow))	Heavy Steering Feel (EPS Warning Light (Yellow))
Steering effort differs between right and left or is uneven	Power steering ECU zero point calibration not completed
	Front tires (improperly inflated, unevenly worn)
	Front wheel alignment (incorrect)
	Front suspension (Lower ball joint)
	Steering gear assembly
	Torque sensor (Electric power steering column sub-assembly)
	Electric power steering column sub-assembly
	Power steering ECU assembly
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 actuator assembly)
	Speed sensor
	Torque sensor (Electric power steering column sub-assembly)
	Power steering ECU assembly
	CAN communication system
Friction sounds occur when turning steering wheel during low speed driving	Power steering motor (Power steering ECU assembly)
	Electric power steering column sub-assembly
	Spiral cable with sensor sub-assembly
	Steering column cover contacting steering wheel assembly
High-pitched sound (squeaking) occurs when turning steering wheel slowly with vehicle stopped	Power steering motor (Power steering ECU assembly)
	Steering wheel installation (incorrect)
Steering wheel vibrates and noise occurs when turning steering wheel from lock to lock	Power steering motor (Power steering ECU assembly)
	Electric power steering column sub-assembly
	Steering wheel installation (incorrect)
EPS warning light remains on	EPS warning light circuit

Calibration

CALIBRATION POWER STEERING ECU INITIAL SETTING (ASSIST MAP WRITING) (USING GTS) NOTICE: If any of the following conditions are met, perform Power Steering ECU Initial Setting (assist map writing): The power steering ECU assembly has been replaced...

Terminals Of Ecu

TERMINALS OF ECU CHECK POWER STEERING ECU ASSEMBLY *a Component without harness connected (Power Steering ECU Assembly) - - (a) Measure the voltage and resistance according to the value(s) in the table below...

Other information:

Toyota Yaris XP210 (2020-2026) Reapir and Service Manual: Starter Relay Signal Compare Failure (P061562)

DESCRIPTION When the STA signal detected by the ECM and by the engine stop and start ECU do not match, the engine stop and start ECU stores DTC P061562 and blinks the stop and start cancel indicator. DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Memory Note P061562 Starter Relay Signal Compare Failure Both of the following conditions are met for 2 seconds or more (1 trip detection logic): Normal communication with the ECM...

Toyota Yaris XP210 (2020-2026) Reapir and Service Manual: Lost Communication with ECM/PCM "A" Missing Message (U010087,U012687,U012987)

DESCRIPTION The AWD ECU assembly receives signals from the ECM, steering sensor and skid control ECU (brake actuator assembly) via CAN communication. DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Memory U010087 Lost Communication with ECM/PCM "A" Missing Message When the ignition switch is ON, the IG1 terminal voltage is 10 V or more and the vehicle speed is 60 km/h (37 mph) or more, signals cannot be received from the ECM for 1 second or more CAN communication system AWD ECU assembly ECM Displayed Yes U012687 Lost Communication with Steering Angle Sensor Module Missing Message When the following continues: When the IG1 terminal voltage is 10 V or more, communication with the steering sensor is impossible for 1 second or more When the IG1 terminal voltage is 10 V or more, a condition in which communication with the steering sensor is impossible occurs 1 time or more within a 5-second period, and this occurs 10 times within 60 seconds CAN communication system AWD ECU assembly Steering sensor Displayed Yes U012987 Lost Communication with Brake System Control Module Missing Message When the IG1 terminal voltage is 10 V or more, communication with the skid control ECU (brake actuator assembly) is impossible for 3 seconds or more CAN communication system AWD ECU assembly Skid control ECU (Brake actuator assembly) Displayed Yes PROCEDURE 1...