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Problem Symptoms Table

ELECTRONIC POWER STEERING SYSTEM 

ELECTRONIC POWER STEERING SYSTEM - PROBLEM SYMPTOMS CHART

Symptom Suspected Area See
Steering is heavy 1. Front tires (Improperly inflated, unevenly worn) FRONT WHEEL ALIGNMENT
2. Front wheel alignment (Incorrect) FRONT WHEEL ALIGNMENT
3. Front suspension (Lower ball joint) REMOVAL
4. Power steering link assembly (Torque sensor, motor rotation angle sensor, power steering motor) (for 2WD) STEERING GEAR (FOR 2WD) 
5. Power steering link assembly (Torque sensor, motor rotation angle sensor, power steering motor) (for 4WD) STEERING GEAR (FOR 4WD) 
6. Steering column assembly (for 2GR-FSE) REMOVAL
7. Steering column assembly (for 3UZ-FE) REMOVAL
8. Battery and power source system -
9. Power source voltage of power steering ECU assembly IG POWER SOURCE CIRCUIT 
10. Power steering ECU assembly POWER STEERING ECU 
11. Vehicle condition (The steering wheel is turned from left to right repeatedly with the vehicle stopped or a heavy load is continuously applied to the vehicle) -
Steering effort differs between right and left, or is uneven 1. Power steering ECU assembly (Steering center point (zero point) is not recorded correctly) CALIBRATION 
2. Front tires (Improperly inflated, unevenly worn) FRONT WHEEL ALIGNMENT
3. Front wheel alignment (Incorrect) FRONT WHEEL ALIGNMENT
4. Front suspension (Lower ball joint) REMOVAL
5. Power steering link assembly (Torque sensor, motor rotation angle sensor, power steering motor) (for 2WD) STEERING GEAR (FOR 2WD) 
6. Power steering link assembly (Torque sensor, motor rotation angle sensor, power steering motor) (for 4WD) STEERING GEAR (FOR 4WD) 
7. Steering column assembly (for 2GR-FSE) REMOVAL
8. Steering column assembly (for 3UZ-FE) REMOVAL
9. Power steering ECU assembly POWER STEERING ECU 
While driving, steering effort does not change in accordance with vehicle speed, or the steering wheel does not return to its centered position easily 1. Front suspension (Lower ball joint) REMOVAL
2. Speed sensor (for 2WD) INSPECTION
3. Speed sensor (for 4WD) INSPECTION
4. Brake actuator (for 2GR-FSE) REMOVAL
5. Brake actuator (for 3UZ-FE) REMOVAL
6. Skid control ECU REMOVAL
7. Power steering link assembly (Torque sensor, motor rotation angle sensor, power steering motor) (for 2WD) STEERING GEAR (FOR 2WD) 
8. Power steering link assembly (Torque sensor, motor rotation angle sensor, power steering motor) (for 4WD) STEERING GEAR (FOR 4WD) 
9. Power steering ECU assembly POWER STEERING ECU 
10. CAN communication system SYSTEM DESCRIPTION
Friction sounds occur when turning the steering wheel during low speed driving 1. Power steering link assembly (Power steering motor) (for 2WD) STEERING GEAR (FOR 2WD) 
2. Power steering link assembly (Power steering motor) (for 4WD) STEERING GEAR (FOR 4WD) 
3. Steering column assembly (for 2GR-FSE) REMOVAL
4. Steering column assembly (for 3UZ-FE) REMOVAL
High-pitched sounds (squeaking) occur when turning the steering wheel slowly with the vehicle stopped 1. Power steering link assembly (Power steering motor) (for 2WD) STEERING GEAR (FOR 2WD) 
2. Power steering link assembly (Power steering motor) (for 4WD) STEERING GEAR (FOR 4WD) 
The steering wheel vibrates and noise occurs when turning the steering wheel with the vehicle stopped 1. Power steering link assembly (Power steering motor) (for 2WD) STEERING GEAR (FOR 2WD) 
2. Power steering link assembly (Power steering motor) (for 4WD) STEERING GEAR (FOR 4WD) 
3. Steering column assembly (for 2GR-FSE) REMOVAL
4. Steering column assembly (for 3UZ-FE) REMOVAL
P/S warning light in the combination meter is always on 1. IG power source circuit IG POWER SOURCE CIRCUIT 
2. Combination meter HOW TO PROCEED WITH TROUBLESHOOTING
3. Power steering ECU assembly POWER STEERING ECU