POWER STEERING SYSTEM, Diagnostic DTC:C1524/24, C1555/25

DTC Code DTC Name
C1524/24 Motor Circuit Malfunction
C1555/25 Motor Relay Welding Failure

DESCRIPTION

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

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Return-to-normal Condition
C1524/24 Motor Circuit Malfunction Short (or open) in motor circuit or abnormal voltage or current in motor circuit

  • Power steering motor assembly

  • Power steering ECU assembly

 On Ignition switch ON again
C1555/25 Motor Relay Welding Failure Motor relay circuit malfunction

  • Power steering motor assembly

  • Power steering ECU assembly

 On Ignition switch ON again

WIRING DIAGRAM

A00YTV6E04

CAUTION / NOTICE / HINT

Note

If the power steering ECU assembly has been replaced, perform assist map writing Click here.

PROCEDURE


  1. INSPECT TIGHTENING TORQUE OF MOTOR TERMINAL BOLT


    1. Disengage the 4 claws to remove the protector.

      Click here

    2. Check that the motor terminal bolts are tightened to the specified torque.

      Click here

      OK
      The motor terminal bolts are tightened to the specified torque.
      Result
      Proceed to
      OK
      NG

    NG

    TIGHTEN BOLT TO SPECIFIED TORQUE Click here

    OK

  2. INSPECT POWER STEERING MOTOR ASSEMBLY


    1. A00YTBHC04
      *1 Power Steering Motor Assembly

      Remove the power steering motor assembly.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (PHA) - 2 (PHB) 25°C (77°F) 12.7 to 17.2 mΩ
      2 (PHB) - 3 (PHC) 25°C (77°F) 12.7 to 17.2 mΩ
      3 (PHC) - 1 (PHA) 25°C (77°F) 12.7 to 17.2 mΩ
      1 (PHA) - Motor case Always 10 kΩ or higher
      2 (PHB) - Motor case Always 10 kΩ or higher
      3 (PHC) - Motor case Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE POWER STEERING MOTOR ASSEMBLY Click here

    OK

  3. READ VALUE USING GTS (MOTOR TERMINAL VOLT)


    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Start the engine.

    4. Turn the GTS on.

    5. Enter the following menus: Chassis / EMPS / Data List.

    6. Select the items "Motor Terminal Volt (U)", "Motor Terminal Volt (V)" and "Motor Terminal Volt (W)" in the Data List and read the value displayed on the GTS.


      Chassis > EMPS > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Motor Terminal Volt(U) Motor terminal voltage (A phase)

      Min.: 0.000 V

      Max.: 98.000 V

      		 Engine running and steering wheel being turned: Value changes within 4 to 35 V range -
      Motor Terminal Volt(V) Motor terminal voltage (B phase)

      Min.: 0.000 V

      Max.: 98.000 V

      		 Engine running and steering wheel being turned: Value changes within 4 to 35 V range -
      Motor Terminal Volt(W) Motor terminal voltage (C phase)

      Min.: 0.000 V

      Max.: 98.000 V

      		 Engine running and steering wheel being turned: Value changes within 4 to 35 V range -

      Chassis > EMPS > Data List
      Tester Display
      Motor Terminal Volt(U)
      Motor Terminal Volt(V)
      Motor Terminal Volt(W)
      Result
      Result Proceed to
      During steering operation, value changes within 4 to 35 V range. A
      During steering operation, voltage is not generated. B

    A

    REPLACE POWER STEERING ECU ASSEMBLY Click here

    B

    REPLACE POWER STEERING MOTOR ASSEMBLY Click here