POWER STEERING SYSTEM, Diagnostic DTC:C1552/22 and C1554/23

DTC Code DTC Name
C1552/22 PIG Power Supply Voltage Malfunction
C1554/23 Power Supply Relay Failure

DESCRIPTION

When a problem occurs in the power steering system, the power source relay circuit is shut off to stop the power assist.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Return-to-normal Condition

C1552/22

PIG Power Supply Voltage Malfunction

PIG power source circuit malfunction inside ECU

  • EPS fuse

  • PIG power source circuit

  • ECU wire sub-assembly

  • Power steering ECU assembly

On

Power switch on (IG) again

C1554/23

Power Supply Relay Failure

Power source relay circuit malfunction

  • EPS fuse

  • PIG power source circuit

  • ECU wire sub-assembly

  • Power steering ECU assembly

On

Power switch on (IG) again

WIRING DIAGRAM

C277339E05

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 (PIG POWER SUPPLY)

    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 "PIG 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

      PIG Power Supply

      Power source voltage to active motor

      Min.: 0.0000 V

      Max.: 20.1531 V

      Power switch on (READY) and steering wheel being turned: 11 to 14 V

      -

      Chassis > EMPS > Data List

      Tester Display

      PIG Power Supply

      OK

      The normal condition value is displayed on the GTS.

    Result

    Proceed to

    OK

    NG
    OK

    CHECK INTERMITTENT PROBLEMS

    Click hereClick hereClick here

    NG

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

    1. C277337C01

      *a

      Front view of wire harness connector

      (to ECU Wire Sub-assembly)

      Disconnect the Ah1 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

      Ah1-1 (PIG) - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK ECU WIRE SUB-ASSEMBLY

    1. C240344C04

      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Connect the Ah1 connector to the ECU wire sub-assembly.

    2. Disconnect the h2 power steering ECU assembly connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      h2-1 (PIG) - Body ground

      Always

      11 to 14 V

    4. 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