Toyota Yaris: Power Steering System / Problem Symptoms Table

Toyota Yaris XP210 (2020-2025) 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 (2020-2025) Reapir and Service Manual: Terminals Of Ecu

TERMINALS OF ECU CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (a) Disconnect the H46 certification ECU (smart key ECU assembly) connector. (b) Measure the voltage and resistance according to the value(s) in the table below. Tester Connection Terminal Description Condition Specified Condition Related Data List Item H46-29 (E) - Body ground Ground Always Below 1 Ω - H46-6 (+B) - H46-29 (E) Power supply Always 11 to 14 V - H45-22 (CUTB) - H46-29 (E) Dark current cut pin* Ignition switch off 11 to 14 V - *: In order to prevent the vehicle auxiliary battery from being depleted when the vehicle is shipped long distances, a fuse that cuts unnecessary electrical load while the vehicle is being shipped is installed in the circuit...

Toyota Yaris XP210 (2020-2025) Owner's Manual: Refueling

Before refueling, close all the doors, windows, and the liftgate/trunk lid, and switch the ignition OFF. To open the fuel-filler lid, pull the remote fuel-filler lid release. To remove the fuel-filler cap, turn it counterclockwise. Attach the removed cap to the inner side of the fuel-filler lid...