POWER STEERING SYSTEM (for 2GR), Diagnostic DTC:C1524, C1555

DTC Code DTC Name
C1524 Motor Circuit Malfunction
C1555 Motor Relay Welding Failure

DESCRIPTION

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

DTC No. DTC Detection Condition Trouble Area
C1524 Short (or open) in motor circuit or abnormal voltage or current in motor circuit

  • Power steering motor assembly

  • Power steering ECU assembly
C1555 Motor relay circuit malfunction

WIRING DIAGRAM

A01HQCSE06

INSPECTION PROCEDURE

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.

    NG

    TIGHTEN BOLT TO SPECIFIED TORQUE

    OK

  2. INSPECT POWER STEERING MOTOR ASSEMBLY


    1. A01HNFUE03
      Text in Illustration
      *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
      a-1 (PHA) - a-2 (PHB) 25°C (77°F) 12.7 to 17.2 mΩ
      a-2 (PHB) - a-3 (PHC) 25°C (77°F) 12.7 to 17.2 mΩ
      a-3 (PHC) - a-1 (PHA) 25°C (77°F) 12.7 to 17.2 mΩ
      a-1 (PHA) - Motor case Always 10 kΩ or higher
      a-2 (PHB) - Motor case Always 10 kΩ or higher
      a-3 (PHC) - Motor case Always 10 kΩ or higher

    NG

    REPLACE POWER STEERING MOTOR ASSEMBLY Click here

    OK

  3. READ VALUE USING TECHSTREAM (MOTOR VOLTAGE)


    1. Turn the engine switch off.

    2. Connect the Techstream to the DLC3.

    3. Start the engine.

    4. Turn the Techstream 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 Techstream.

      EMPS
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Motor Terminal Volt (U)

      Motor terminal voltage (A phase)/

      Min.: 0 V

      Max.: 98.000 V

      		 Value changes within 4 to 35 V range Engine running and steering wheel being turned
      Motor Terminal Volt (V)

      Motor terminal voltage (B phase)/

      Min.: 0 V

      Max.: 98.000 V

      		 Value changes within 4 to 35 V range Engine running and steering wheel being turned
      Motor Terminal Volt (W)

      Motor terminal voltage (C phase)/

      Min.: 0 V

      Max.: 98.000 V

      		 Value changes within 4 to 35 V range Engine running and steering wheel being turned
      Result
      Condition Proceed to
      During steering operation, value changes within 4 to 35 V range A
      During steering operation, voltage is not generated B

    B

    REPLACE POWER STEERING MOTOR ASSEMBLY Click here

    A

    REPLACE POWER STEERING ECU ASSEMBLY Click here