POWER STEERING SYSTEM EPS Warning Light Circuit

DESCRIPTION

If the power steering ECU assembly detects a malfunction, the EPS warning light comes on. At this time, the power steering ECU assembly stores a DTC in its memory.

WIRING DIAGRAM

A011VJ8E06

INSPECTION PROCEDURE

Note

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

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. CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

    1. Check for DTCs Click here.

      OK
      DTC is not output.
    NG

    GO TO CAN COMMUNICATION SYSTEM Click here

    OK

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

    1. Disconnect the Ij2 connector from the ECU wire sub-assembly.

      A011YTIE02

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Ij2-5 (IG) - Body ground Power switch on (IG) 9 to 16 V
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECU Wire Sub-assembly)
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK ECU WIRE SUB-ASSEMBLY

    1. Connect the Ij2 connector to the ECU wire sub-assembly.

      A011WSPE02

    2. Disconnect the power steering ECU assembly j3 and j2 connectors.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      j3-1 (IG) - Body ground Power switch on (IG) 9 to 16 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      j2-2 (PGND) - Body ground Always Below 1 Ω
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)
    NG

    REPAIR OR REPLACE ECU WIRE SUB-ASSEMBLY Click here

    OK

  5. INSPECT COMBINATION METER ASSEMBLY

    1. Reconnect the power steering ECU assembly connector.

    2. Perform the Active Test of the combination meter assembly using the Techstream Click here.

    3. Check the combination meter assembly.

      OK
      The EPS warning light turns on or off in accordance with the Techstream operation.

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part Click here.

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

    REPLACE POWER STEERING ECU ASSEMBLY Click here