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Problem Symptoms Table

ELECTRONIC POWER STEERING SYSTEM 

PROBLEM SYMPTOMS TABLE

Symptom Suspected area Reference
Steering is heavy.
  1. Front tires (Improperly inflated, unevenly worm)
  2. Front wheel alignment (Incorrect)
  3. Front suspension
  4. Power steering gear assembly (2WD)
  5. Power steering gear assembly (4WD)
  6. Steering column assembly (Manual tilt)
  7. Steering column assembly (Power tilt and Power telescopic)
  8. Battery and power source system
  9. Power source voltage of power steering ECU assembly
  10. Power steering ECU assembly
  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)
  1. FRONT WHEEL ALIGNMENT
  2. FRONT WHEEL ALIGNMENT
  3. REMOVAL
  4. REMOVAL 
  5. REMOVAL 
  6. REMOVAL
  7. REMOVAL
  8. -
  9. PS Warning Light Remains ON 
  10. REMOVAL 
  11. -
  1. Power steering ECU assembly (Steering center point is not recorded correctly)
  2. Front tires (Improperly inflated, unevenly worm)
  3. Front wheel alignment (Incorrect)
  4. Front Suspension
  5. Power steering gear assembly (2WD)
  6. Power steering gear assembly (4WD)
  7. Steering column assembly (Manual tilt)
  8. Steering column assembly (Power tilt and Power telescopic)
  9. Power steering ECU assembly
  1. CALIBRATION 
  2. FRONT WHEEL ALIGNMENT
  3. FRONT WHEEL ALIGNMENT
  4. REMOVAL
  5. REMOVAL 
  6. REMOVAL 
  7. REMOVAL
  8. REMOVAL
  9. REMOVAL 
While driving, steering effort does not change in accordance with vehicle speed, or the steering wheel does not return to its centured position easily.
  1. Speed sensor
  2. Power steering gear assembly (2WD)
  3. Power steering gear assembly (4WD)
  4. Power steering ECU assembly
  1. -
  2. REMOVAL 
  3. REMOVAL 
  4. REMOVAL 
Friction sounds occur when turning the steering wheel during low speed driving.
  1. Power steering gear assembly (2WD)
  2. Power steering gear assembly (4WD)
  3. Power steering ECU assembly
  1. REMOVAL 
  2. REMOVAL 
  3. REMOVAL 
High-pitched sounds (squeaking) occur when turning the steering wheel slowly with the stepped.
  1. Power steering gear assembly (2WD)
  2. Power steering gear assembly (4WD)
  1. REMOVAL 
  2. REMOVAL 
The steering wheel vibrates and noise occur when turning the steering wheel with the vehicle stopped.
  1. Power steering gear assembly (2WD)
  2. Power steering gear assembly (4WD)
  3. Steering column assembly (Manual tilt)
  4. Steering column assembly (Power tilt and Power telescopic)
  1. REMOVAL 
  2. REMOVAL 
  3. REMOVAL
  4. REMOVAL
PS warning light remains on.
  1. PS warning light remains on
  1. PS Warning Light Remains ON 
PS warning light does not come on.
  1. PS warning light does not come on
  1. PS Warning Light Does Not Come ON 
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