Tech Tips
Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
Inspect the fuses and relays related to this system before inspecting the suspected areas below.
| Symptom | Suspected Area | Link |
|---|---|---|
| Heavy steering | Front tires (improperly inflated, unevenly worn) | |
| Front wheel alignment (incorrect) | ||
| Front suspension (lower ball joint) | ||
| Steering gear assembly | ||
| Torque sensor (built into electric power steering column sub-assembly) | - | |
| Power steering motor (built into power steering ECU assembly) | ||
| Auxiliary battery and power source system | - | |
| Power steering ECU assembly power source voltage | ||
| Power steering ECU assembly | ||
| Steering wheel is turned with vehicle stopped or heavy load is continuously applied to vehicle | - | |
| Steering effort differs between turning right and left, or steering effort is uneven | Calibration of torque sensor zero point are not completed | |
| Front tires (improperly inflated, unevenly worn) | ||
| Front wheel alignment (incorrect) | ||
| Front suspension (lower ball joint) | ||
| Steering gear assembly | ||
| Torque sensor (built into electric power steering column sub-assembly) | - | |
| Electric power steering column sub-assembly | ||
| Power steering motor (built into power steering ECU assembly) | ||
| Power steering ECU assembly | ||
| While driving, steering effort does not change in accordance with vehicle speed or the steering wheel does not return properly | Skid control ECU (brake booster with master cylinder assembly) | |
| Speed sensor circuit | ||
| Torque sensor (built into electric power steering column sub-assembly) | - | |
| Power steering motor (built into power steering ECU assembly) | ||
| Power steering ECU assembly | ||
| CAN communication system (for LHD) | ||
| CAN communication system (for RHD) | ||
| Knocking (or clunking) sound occurs when turning the steering wheel back and forth while power steering is operating | Front suspension (lower ball joint) | |
| Steering intermediate shaft | - | |
| Power steering ECU assembly | ||
| Noise occurs when turning the steering wheel during low-speed driving | Power steering motor (built into power steering ECU assembly) | |
| Electric power steering column sub-assembly | ||
| Spiral cable with sensor sub-assembly | ||
| Friction between the steering wheel and steering column cover | - | |
| Friction occurs when turning the steering wheel during low-speed driving | Power steering motor (built into power steering ECU assembly) | |
| Electric power steering column sub-assembly | ||
| High-pitched sound (squeaking) occurs when turning the steering wheel slowly with the vehicle stopped | Power steering motor (built into power steering ECU assembly) | |
| Steering wheel installation condition | ||
| Steering wheel vibrates and noise occurs when turning the steering wheel from lock to lock with the vehicle stopped | Power steering motor (built into power steering ECU assembly) | |
| Electric power steering column sub-assembly | ||
| Steering wheel installation condition | ||
| DTCs cannot be output (terminals TC and CG of the DLC3 are connected) | TC and CG terminal circuit | |
| IG power source circuit | ||
| Combination meter assembly | ||
| Signal check cannot be done (terminals TS and CG of the DLC3 are connected) | TS and CG terminal circuit | |
| Power steering ECU assembly | ||
| Power steering warning light remains on | Auxiliary battery and power source system | - |
| Power steering warning light circuit |