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Problem Symptoms Table

ELECTRONIC POWER STEERING SYSTEM 

PROBLEM SYMPTOMS CHART

Symptom Suspected area See
Steering is heavy. 1. Front tires (Improperly inflated, unevenly worm) FRONT WHEEL ALIGNMENT
2. Front wheel alignment (Incorrect) FRONT WHEEL ALIGNMENT
3. Front suspension INSPECTION
4. Power steering gear assembly (2WD) STEERING GEAR (FOR 2WD) 
5. Power steering gear assembly (4WD) STEERING GEAR (FOR 4WD) 
6. Steering column assembly (Manual tilt) REMOVAL
7. Steering column assembly (Power tilt and Power telescopic) REMOVAL
8. Battery and power source system -
9. Power source voltage of power steering ECU assembly PS WARNING LIGHT REMAINS ON 
10. Power steering ECU assembly POWER STEERING ECU 
11. Vehicle condition (The steering wheel is turned from left to right repeatedly with the vehicles 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 is not recorded correctly) CALIBRATION 
2. Front tires (Improperly inflated, unevenly worm) FRONT WHEEL ALIGNMENT
3. Front wheel alignment (Incorrect) FRONT WHEEL ALIGNMENT
4. Front suspension INSPECTION
5. Power steering gear assembly (2WD) STEERING GEAR (FOR 2WD) 
6. Power steering gear assembly (4WD) STEERING GEAR (FOR 4WD) 
7. Steering column assembly (Manual tilt) REMOVAL
8. Steering column assembly (Power tilt and Power telescopic) 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. Speed sensor -
2. Skid control ECU SKID CONTROL ECU (W/ VDIM)
3. Power steering gear assembly (2WD) STEERING GEAR (FOR 2WD) 
4. Power steering gear assembly (4WD) STEERING GEAR (FOR 4WD) 
5. Power steering ECU assembly POWER STEERING ECU 
Friction sounds occur when turning the steering wheel during low speed driving. 1. Power steering gear assembly (2WD) STEERING GEAR (FOR 2WD) 
2. Power steering gear assembly (4WD) STEERING GEAR (FOR 4WD) 
3. Power steering ECU assembly POWER STEERING ECU 
High-pitched sounds (squeaking) occur when turning the steering wheel slowly with the stepped. 1. Power steering gear assembly (2WD) STEERING GEAR (FOR 2WD) 
2. Power steering gear assembly (4WD) STEERING GEAR (FOR 4WD) 
The steering wheel vibrates and noise occur when turning the steering wheel with the vehicle stopped. 1. Power steering gear assembly (2WD) STEERING GEAR (FOR 2WD) 
2. Power steering gear assembly (4WD) STEERING GEAR (FOR 4WD) 
3. Steering column assembly (Manual tilt) REMOVAL
4. Steering column assembly (Power tilt and Power telescopic) REMOVAL
PS warning light remains on. 1. PS warning light remains on PS WARNING LIGHT REMAINS ON 
PS warning light does not come on. 1. PS warning light does not come on PS WARNING LIGHT DOES NOT COME ON