POWER STEERING SYSTEM (for 2AR-FSE), Diagnostic DTC:C1555/25

DTC Code DTC Name
C1555/25 Motor Relay Welding Failure

DESCRIPTION

The power steering ECU assembly supplies current to the power steering motor.

DTC Code DTC Detection Condition Trouble Area
C1555/25 A motor relay malfunction is detected.

  • Harness or connector

  • Power steering motor (built into power steering link assembly)

  • Power steering ECU assembly

Tech Tips

If there are any tears or holes in the rack boots, water or other foreign material may enter the interior of the power steering link assembly and cause a malfunction.

WIRING DIAGRAM

A01FTC6E05

INSPECTION PROCEDURE

Note


  • If the power steering ECU assembly is replaced with a new one, perform assist map writing, clear the motor rotation angle sensor calibration value, initialize the motor rotation angle sensor value and calibrate the torque sensor zero point Click here.

  • If the power steering link assembly is replaced, clear the motor rotation angle sensor calibration value, initialize the motor rotation angle sensor value and calibrate the torque sensor zero point Click here.

PROCEDURE


  1. CHECK CONNECTORS


    1. Check the connection of the power steering ECU assembly and power steering link assembly connectors.

    2. Visually inspect the terminals of the power steering ECU assembly and power steering link assembly connectors.

      Result

      Result

      Proceed to
      Normal A
      Connectors not properly connected B
      Power steering ECU assembly connector terminals abnormal C
      Power steering link assembly connector terminals abnormal D

    B

    CONNECT CONNECTORS CORRECTLY

    C

    REPLACE POWER STEERING ECU ASSEMBLY Click here

    D

    REPLACE POWER STEERING LINK ASSEMBLY Click here

    A

  2. CHECK HARNESS AND CONNECTOR (POWER STEERING ECU ASSEMBLY - POWER STEERING MOTOR)


    1. Disconnect the C8 power steering ECU assembly connector.

    2. Disconnect the C1 power steering motor connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      C1-1 (W) - C8-2 (W) Always Below 1 Ω
      C1-2 (V) - C8-1 (V) Always Below 1 Ω
      C1-3 (U) - C8-3 (U) Always Below 1 Ω
      C1-1 (W) or C8-2 (W) - Body ground Always 10 kΩ or higher
      C1-2 (V) or C8-1 (V) - Body ground Always 10 kΩ or higher
      C1-3 (U) or C8-3 (U) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT POWER STEERING LINK ASSEMBLY (POWER STEERING MOTOR)


    1. Disconnect the C1 power steering motor connector.

    2. A01FVQ5E01
      Text in Illustration
      *1 Power steering link assembly
      *a Area to set negative probe
      *b

      Component without harness connected

      (Power Steering Motor)

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (W) - 3 (U) Always 0.07 to 10 Ω
      2 (V) - 1 (W) Always 0.07 to 10 Ω
      3 (U) - 2 (V) Always 0.07 to 10 Ω
      1 (W) - Body ground* Always 100 kΩ or higher
      2 (V) - Body ground* Always 100 kΩ or higher
      3 (U) - Body ground* Always 100 kΩ or higher

      *: Touch the negative probe to the power steering link assembly housing at the position shown in the illustration to perform the measurement.


    NG

    REPLACE POWER STEERING LINK ASSEMBLY Click here

    OK

  4. CHECK POWER STEERING LINK ASSEMBLY (CHECK FOR HOLE IN RACK BOOTS)


    1. Remove the power steering link assembly Click here.

    2. Clean off any dirt or foreign matter attached to the rack boots.

    3. Move the rack ends and check that there are no holes in the rack boots.

      OK
      There are no tears or holes.

    NG

    REPLACE POWER STEERING LINK ASSEMBLY Click here

    OK

    REPLACE POWER STEERING ECU ASSEMBLY Click here