POWER STEERING SYSTEM, Diagnostic DTC:C1551

DTC Code DTC Name
C1551 IG Power Supply Voltage

DESCRIPTION

The power steering ECU assembly distinguishes the power switch status as on (IG) or off through the IG power source circuit.

DTC No. DTC Detection Condition Trouble Area
C1551 Open or short in IG power source circuit with power switch on (IG)

  • EPS-IG1 fuse

  • IG power source circuit

  • ECU wire sub-assembly

  • Power steering ECU assembly

WIRING DIAGRAM

A0007O8E16

CAUTION / NOTICE / HINT

Note

If the power steering ECU assembly has been replaced with a new one, perform assist map writing and torque sensor zero point calibration Click here.

Tech Tips

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.

    NG

    CONNECT CONNECTOR OR INSTALL GROUND WIRE Click here

    OK

  2. READ VALUE USING GTS


    1. Turn the power switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    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.

      EMPS
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      IG Power Supply

      IG power source voltage/

      Min.: 0.0000 V

      Max.: 20.1531 V

      		 8 to 16 V Power switch on (IG)
      OK
      The normal condition value is displayed on the GTS.

    OK

    REPLACE POWER STEERING ECU ASSEMBLY Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - ECU WIRE SUB-ASSEMBLY)


    1. A0008FWE03
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECU Wire Sub-assembly)

      Disconnect the Hc2 ECU wire sub-assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Hc2-5 (IG) - Body ground Power switch on (IG) 8 to 16 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK ECU WIRE SUB-ASSEMBLY (POWER STEERING ECU ASSEMBLY - BODY GROUND)


    1. A00066FE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Disconnect the c2 power steering ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      c2-2 (PGND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE ECU WIRE SUB-ASSEMBLY Click here

    OK

  5. INSPECT ECU WIRE SUB-ASSEMBLY


    1. A000801E07

      Disconnect the c1 power steering ECU assembly connector.

    2. A0003KME09
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)
      *b

      Front view of wire harness connector

      (to Vehicle Wire Harness)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      c1-1 (IG) - Hc2-5 (IG) Always Below 1 Ω

    OK

    REPLACE POWER STEERING ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE ECU WIRE SUB-ASSEMBLY Click here