POWER STEERING SYSTEM, Diagnostic DTC:C1551/25

DTC Code DTC Name
C1551/25 IG Power Supply Voltage Malfunction

DESCRIPTION

The power steering ECU assembly distinguishes the ignition switch status as ON or off through the IG power source circuit.

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Return-to-normal Condition
C1551/25 IG Power Supply Voltage Malfunction IG power source circuit malfunction inside ECU

  • EPS-IG fuse (w/o Stop and start system)

  • IG power source circuit

  • ECU wire sub-assembly

  • Power steering ECU assembly

 On Ignition switch ON again

WIRING DIAGRAM

A01V7I5E01

CAUTION / NOTICE / HINT

Note


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

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CHECK CONNECTOR CONNECTION CONDITION AND GROUND WIRE


    1. Check the connection condition of the ECU wire sub-assembly and power steering ECU assembly connectors.

      OK
      The ECU wire sub-assembly and power steering ECU assembly connectors are securely connected.

    2. Check that the ground wire is securely installed with the bolt.

      Click here

      OK
      The ground wire is securely installed with the bolt.
      Result
      Proceed to
      OK
      NG

    NG

    CONNECT CONNECTOR OR INSTALL GROUND WIRE Click here

    OK

  2. READ VALUE USING GTS (IG POWER SUPPLY)


    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the GTS on.

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

    6. Select the item "IG power supply" 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
      IG Power Supply ECU power source voltage

      Min.: 0.0000 V

      Max.: 20.1531 V

      		 Ignition switch ON: 11 to 14 V -

      Chassis > EMPS > Data List
      Tester Display
      IG Power Supply
      OK
      The normal condition value is displayed on the GTS.
      Result
      Proceed to
      OK
      NG

    OK

    CHECK INTERMITTENT PROBLEMS Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY)


    1. A01V9M7C01
      *a

      Front view of wire harness connector

      (to ECU Wire Sub-assembly)

      Disconnect the hG1 ECU wire sub-assembly connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      hG1-5 (IG) - Body ground Ignition switch ON 11 to 14 V
      Result
      Proceed to
      OK
      NG (w/o Stop and Start System)
      NG (w/ Stop and Start System)

    NG (w/o Stop and Start System)

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    NG (w/ Stop and Start System)

    GO TO STOP AND START SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) for 2WW: Click here
    GO TO STOP AND START SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) for 3ZR-FAE: Click here

    OK

  4. CHECK ECU WIRE SUB-ASSEMBLY


    1. A01V9H7C03
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Connect the hG1 connector to the ECU wire sub-assembly.

    2. Disconnect the h1 and h2 power steering ECU assembly connectors.

    3. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      h1-1 (IG) - Body ground Ignition switch ON 11 to 14 V

    5. Turn the ignition switch off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      h2-2 (PGND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POWER STEERING ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE ECU WIRE SUB-ASSEMBLY Click here