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Fail-Safe Chart

When a problem occurs in the electronic motor power steering system, the P/S warning is indicated on the multi-display, the master warning light on the combination meter comes on, and steering power assist is stopped, fixed at a particular point, or decreased simultaneously to protect the system.

Electronic power steering system 

FAIL-SAFE CHART

DTC No. Malfunction Fail-safe
C1511
C1512
C1513
C1514
C1517
Torque sensor malfunction Power assist stops.
C1524 Motor malfunction Power assist stops.
C1531
C1532
Power steering ECU malfunction Power assist stops.
C1533 Temperature sensor malfunction in power steering ECU Amount of power assist is limited.
C1551 IG power source voltage error Power assist stops.
C1552 PIG power source voltage error Power assist stops.
C1554 Power source relay malfunction Power assist stops.
C1555 Motor relay malfunction Power assist stops.
U0073 CAN bus malfunction Amount of power assist is fixed for a speed of 43 mph (70 km/h).
U0121 Skid control ECU communication error Amount of power assist is fixed for a speed of 43 mph (70 km/h).
- Extremely high temperature in ECU Amount of power assist is limited until ECU temperature goes down.
- Power source voltage drop Power assist is interrupted, but normal power assist is resumed when voltage returns.

HINT:

Amount of power assist may be decreased to prevent the motor and ECUs from overheating if the steering wheel is continuously turned when the vehicle is either stopped or driven at a low speed, or if the steering wheel is kept at either full lock position for a long time. In that case, the amount of power assist returns to normal if the steering wheel is not turned for approximately 10 minutes with the engine idling.