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Problem Symptoms Table

HINT:

Use PROBLEM SYMPTOM TABLE  to help determine the cause of the problem. The numbers indicate likely causes of the problem in order. Check each part in order. If necessary, repair or replace the faulty parts.

POWER STEERING SYSTEM: 

PROBLEM SYMPTOM TABLE

Symptom Suspected area Reference
Steering is heavy.
  1. Front tires (Improperly inflated, unevenly worn)
  2. Front wheel alignment (Incorrect)
  3. Front suspension (Lower ball joint)
  4. Steering column assembly (for Power Tilt and Power Telescopic)
  5. Steering column assembly (for Manual Tilt and Manual Telescopic)
  6. Torque sensor (Built into steering gear assembly)
  7. Power steering motor
  8. Speed sensor
  9. Skid control ECU
  10. Battery and power source system
  11. Power steering ECU power source voltage and relay
  12. Power steering ECU
  1. INSPECTION
  2. FRONT WHEEL ALIGNMENT
  3. REMOVAL
  4. REMOVAL
  5. REMOVAL
  6. -
  7. -
  8. -
  9. -
  10. -
  11. -
  12. -
Steering effort differs between right and left or is uneven
  1. Calibration of turning angle sensor output and torque sensor zero point is not completed
  2. Front tires (Improperly inflated, unevenly worn)
  3. Front wheel alignment (Incorrect)
  4. Front suspension (Lower ball joint)
  5. Power steering gear (for 2WD)
  6. Power steering gear (for 4WD)
  7. Torque sensor (Built into steering link assembly)
  8. Steering column assembly (for Power Tilt and Power Telescopic)
  9. Steering column assembly (for Manual Tilt and Manual Telescopic)
  10. Power steering motor
  11. Power steering ECU
  1. CALIBRATION 
  2. INSPECTION
  3. FRONT WHEEL ALIGNMENT
  4. REMOVAL
  5. REMOVAL 
  6. REMOVAL 
  7. -
  8. REMOVAL
  9. REMOVAL
  10. -
  11. -
While driving, steering effort does not change in accordance with vehicle speed or the steering wheel does not return properly.
  1. Front suspension (Lower ball joint)
  2. Speed sensor
  3. Skid control ECU
  4. Combination meter
  5. Engine speed detection circuit
  6. Torque sensor (Built into steering gear assembly)
  7. Power steering motor
  8. Power steering ECU
 A knocking (or cranking) sound occurs when turning the steering wheel during low speed driving
  1. REMOVAL
  2. -
  3. -
  4. -
  5. -
  6. -
  7. -
  8. -
A knocking (or cranking) sound occurs when turning the steering wheel back and forth while power steering is in operation.
  1. Front suspension (Lower ball joint)
  2. Steering intermediate shaft
  3. Power steering gear (for 2WD)
  4. Power steering gear (for 4WD)
  1. REMOVAL
  2. -
  3. REMOVAL 
  4. REMOVAL 
Noise occurs when turning the steering wheel during low speed driving.
  1. Power steering gear (for 2WD)
  2. Power steering gear (for 4WD)
  3. Steering column assembly (for Power Tilt and Power Telescopic)
  4. Steering column assembly (for Manual Tilt and Manual Telescopic)
  1. REMOVAL 
  2. REMOVAL 
  3. REMOVAL
  4. REMOVAL
A high-pitched sound (squeaking) occurs when turning the steering wheel slowly with the vehicle stopped.
  1. Power steering motor
  1. -
The steering wheel vibrates and noise occurs when turning the steering wheel from lock to lock.
  1. Power steering gear (for 2WD)
  2. Power steering gear (for 4WD)
  3. Steering column assembly (for Power Tilt and Power Telescopic)
  4. Steering column assembly (for Manual Tilt and Manual Telescopic)
  1. REMOVAL 
  2. REMOVAL 
  3. REMOVAL
  4. REMOVAL
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