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Problem Symptoms Table

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Power Steering System 

PROBLEM SYMPTOMS CHART - POWER STEERING SYSTEM

Symptom Suspected Area See
Steering is heavy Front tires (Improperly inflated, unevenly worn) INSPECTION
Front wheel alignment (Incorrect) FRONT WHEEL ALIGNMENT
Front suspension (Lower ball joint) REMOVAL
Power steering gear assembly REMOVAL
Steering column assembly REMOVAL
Torque sensor (Built into steering gear assembly) DTC C1511 TORQUE SENSOR CIRCUIT MALFUNCTION 
Power steering motor REMOVAL
Speed sensor TEST MODE PROCEDURE
Skid control ECU REMOVAL
Battery and power source system -
Power steering ECU power source voltage and relay DTC C1552 PIG POWER SUPPLY VOLTAGE MALFUNCTION 
Power steering ECU assembly POWER STEERING ECU 
Steering effort differs between right and left or is uneven Calibration of turning angle sensor output and torque sensor CALIBRATION 
Front tires (Improperly inflated, unevenly worn) INSPECTION
Front wheel alignment (Incorrect) FRONT WHEEL ALIGNMENT
Front suspension (Lower ball joint) REMOVAL
Power steering gear REMOVAL
Torque sensor (Built into steering link assembly) DTC C1511 TORQUE SENSOR CIRCUIT MALFUNCTION 
Steering column assembly REMOVAL
Power steering motor REMOVAL
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 properly Front suspension (Lower ball joint) REMOVAL
Speed sensor TEST MODE PROCEDURE
Skid control ECU REMOVAL
Combination meter REMOVAL
Torque sensor (Built into steering gear assembly) DTC C1511 TORQUE SENSOR CIRCUIT MALFUNCTION 
Power steering motor REMOVAL
Power steering gear assembly REMOVAL
Power steering ECU assembly POWER STEERING ECU 
A knocking (or cranking) sound occurs when turning the steering wheel back and forth while power steering is in operation Front suspension (Lower ball joint) REMOVAL
Steering intermediate shaft REMOVAL
Power steering gear REMOVAL
Noise occurs when turning the steering wheel during low speed driving Power steering gear REMOVAL
Steering column assembly REMOVAL
Power steering ECU assembly POWER STEERING ECU 
High-pitched sounds (squeaking) occur when turning the steering wheel slowly with the stepped Power steering gear assembly REMOVAL
Power steering motor REMOVAL
The steering wheel vibrates and noise occurs when turning the steering wheel from lock to lock Power steering gear assembly REMOVAL
Steering column assembly REMOVAL
P/S warning light remains on PS warning light remains on PS WARNING LIGHT REMAINS ON 
P/S warning light does not come on PS warning light does not come on PS WARNING LIGHT DOES NOT COME ON