Electronic Power Steering System Fail-Safe Chart

Steering. Lexus Is250, Is220D. Gse20 Ale20
Power Steering. Lexus Is250, Is220D. Gse20 Ale20

Electronic Power Steering System -- Fail-Safe Chart


If a problem occurs in the electronic power steering system, the P/S warning light will come on in the combination meter and steering power assistance will be stopped, fixed at a particular point, or decreased simultaneously to protect the system.

DTC No.
Malfunction
Fail-safe
C1511
Torque Sensor Circuit Malfunction
Power assistance stops.
C1512
C1513
C1521
Motor Circuit Malfunction
C1522
C1523
C1524
C1528
Motor Rotation Angle Sensor Malfunction
C1531
ECU Malfunction
C1532
C1555
Motor Relay Welding Failure
C1533
ECU Malfunction
System overheat prevention control continues without using the substrate temperature sensor.
C1534
ECU Malfunction
Torque sensor zero point and rotation angle sensor calibration value are set to the default values.
C1541
Vehicle Speed Signal Malfunction
Amount of power assistance is fixed for a speed of 100 km/h (62 mph).
C1521
Lost Communication With Anti-lock Brake System (ABS) Control Module
HINT:
The amount of power assistance 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 assistance will return to normal if the steering wheel is not turned for approximately 10 minutes with the engine idling.