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DTC C0023-14: Stop Lamp Control Circuit Short To Ground Or Open: Procedure

  1. VERIFY REAR MAIN BODY ECU DTCS AGAIN 
    1. Clear the DTC for the main body ECU using the Techstream.

      Refer to DTC CHECK / CLEAR

      Body Electrical > Body Control Module > Clear DTCs 

    2. Depress the brake pedal.
    3. Retrieve the main body ECU DTCs using the Techstream.

      Refer to DTC CHECK / CLEAR

      Body Electrical > Body Control Module > Trouble Codes 

    4. Is the same DTC displayed?

      Result

      Result Proceed to
      With rear combination light assembly (bulb type) Yes(A)
      With rear combination light assembly (LED type) Yes(B)
      - No

    Result:  3

    Yes(B) 

    See step  4

    Result:  2

    No 

    See step  18

    Result:  1

    Yes(A) 

    See step  2

  2. VISUALLY INSPECT BRAKE LIGHT BULB (LH) 
    1. Visually inspect the brake light bulb (LH)
    2. Is the brake light bulb (LH) normal?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  34

    Result:  1

    Yes 

    See step  3

  3. VISUALLY INSPECT BRAKE LIGHT BULB (RH) 
    1. Visually inspect the brake light bulb (RH)
    2. Is the brake light bulb (RH) normal?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  33

    Result:  1

    Yes 

    See step  4

  4. INSPECT HIGH MOUNTED STOP LIGHT ASSEMBLY CONNECTOR CONDITION 
    1. Switch the ignition off.
    2. Disconnect the negative battery cable

      Refer to REMOVAL

    3. Disconnect the high mounted stop light assembly connector.
    4. Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
    5. Is the connector normal?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  32

    Result:  1

    Yes 

    See step  5

  5. INSPECT BRAKE LIGHT (LH) CONNECTOR CONDITION 
    1. Disconnect the brake light (LH) connector.
    2. Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
    3. Is the connector normal?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  31

    Result:  1

    Yes 

    See step  6

  6. INSPECT BRAKE LIGHT (RH) CONNECTOR CONDITION 
    1. Disconnect the brake light (RH) connector
    2. Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
    3. Is the connector normal?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  30

    Result:  1

    Yes 

    See step  7

  7. INSPECT MAIN BODY ECU CONNECTOR CONDITION 
    1. Disconnect the main body ECU connector.
    2. Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
    3. Is the connector normal?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  29

    Result:  1

    Yes 

    See step  8

  8. INSPECT BRAKE LIGHT CIRCUIT FOR SHORT TO GROUND 
    1. Verify that the high mounted stop light assembly, brake light (LH), brake light (RH) and main body ECU connectors are disconnected.
    2. Inspect for continuity between main body ECU terminal E1-30 (wiring harness-side) and body ground.
    3. Is there continuity?

      Result

      Result
      Yes
      No

    Result:  2

    Yes 

    See step  28

    Result:  1

    No 

    See step  9

  9. INSPECT BRAKE LIGHT CIRCUIT FOR SHORT TO POWER SUPPLY 
    1. Verify that the high mounted stop light assembly, brake light (LH), brake light (RH) and main body ECU connectors are disconnected.
    2. Connect the negative battery cable

      Refer to INSTALLATION

    3. Switch the ignition ON (engine off or on).
    4. Measure the voltage at the main body ECU terminal E1-30 (wiring harness-side).
    5. Is the voltage 0 V?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  27

    Result:  1

    Yes 

    See step  10

  10. INSPECT BRAKE LIGHT CIRCUIT FOR OPEN CIRCUIT 
    1. Switch the ignition off.
    2. Disconnect the negative battery cable.

      Refer to REMOVAL

    3. Verify that the high mounted stop light assembly, brake light (LH), brake light (RH) and main body ECU connectors are disconnected.
    4. Inspect for continuity between the following terminals (wiring harness-side):
      • Brake light (LH) terminal E37-3 - main body ECU terminal E1-30
      • Brake light (RH) terminal E38-3 - main body ECU terminal E1-30
      • High mounted stop light assembly terminal E46-2 - main body ECU terminal E1-30
    5. Is there continuity?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  26

    Result:  1

    Yes 

    See step  11

  11. INSPECT HIGH MOUNTED STOP LIGHT ASSEMBLY FOR SHORT TO GROUND 
    1. Verify that the high mounted stop light assembly, brake light (LH), brake light (RH) and main body ECU connectors are disconnected.
    2. Connect the high mounted stop light assembly connector.
    3. Inspect for continuity between main body ECU terminal E1-30 (wiring harness-side) and body ground.
    4. Is there continuity?

      Result

      Result
      Yes
      No

    Result:  2

    Yes 

    See step  25

    Result:  1

    No 

    See step  12

  12. INSPECT HIGH MOUNTED STOP LIGHT ASSEMBLY FOR SHORT TO POWER SUPPLY 
    1. Verify that the brake light (LH), brake light (RH) and main body ECU connectors are disconnected.
    2. Connect the negative battery cable.

      Refer to INSTALLATION

    3. Switch the ignition ON (engine off or on).
    4. Measure the voltage at the main body ECU terminal E1-30 (wiring harness-side).
    5. Is the voltage 0 V?

      Result

      Result Proceed to
      With rear combination light (LED type) Yes (A)
      With rear combination light (bulb type) Yes (B)
      - No

    Result:  1

    Yes (B) 

    See step  17

    Result:  2

    No 

    See step  24

    Result:  3

    Yes (A) 

    See step  13

  13. INSPECT BRAKE LIGHT (LH) FOR SHORT TO GROUND 
    1. Switch the ignition off.
    2. Disconnect the negative battery cable.

      Refer to REMOVAL

    3. Verify that the brake light (LH), brake light (RH) and main body ECU connectors are disconnected.
    4. Connect the brake light (LH) connector.
    5. Inspect for continuity between main body ECU terminal E1-30 (wiring harness-side) and body ground.
    6. Is there continuity?

      Result

      Result
      Yes
      No

    Result:  2

    Yes 

    See step  23

    Result:  1

    No 

    See step  14

  14. INSPECT BRAKE LIGHT (LH) FOR SHORT TO POWER SUPPLY 
    1. Verify that the brake light (RH) and main body ECU connectors are disconnected.
    2. Connect the negative battery cable

      Refer to INSTALLATION

    3. Switch the ignition ON (engine off or on).
    4. Measure the voltage at the main body ECU terminal E1-30 (wiring harness-side).
    5. Is the voltage 0 V?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  22

    Result:  1

    Yes 

    See step  15

  15. INSPECT BRAKE LIGHT (RH) FOR SHORT TO GROUND 
    1. Switch the ignition off.
    2. Disconnect the negative battery cable.

      Refer to REMOVAL

    3. Verify that the brake light (RH) and main body ECU connectors are disconnected
    4. Connect the brake light (RH) connector.
    5. Inspect for continuity between main body ECU terminal E1-30 (wiring harness-side) and body ground.
    6. Is there continuity?

      Result

      Result
      Yes
      No

    Result:  2

    Yes 

    See step  21

    Result:  1

    No 

    See step  16

  16. INSPECT BRAKE LIGHT (RH) FOR SHORT TO POWER SUPPLY 
    1. Verify that main body ECU connector is disconnected
    2. Connect the negative battery cable.

      Refer to INSTALLATION

    3. Switch the ignition ON (engine off or on).
    4. Measure the voltage at the main body ECU terminal E1-30 (wiring harness-side).
    5. Is the voltage 0 V?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  20

    Result:  1

    Yes 

    See step  17

  17. VERIFY THAT REPAIRS HAVE BEEN COMPLETED 
    1. Always reconnect all disconnected connectors.
    2. Connect the negative battery cable.

      Refer to INSTALLATION

    3. Clear the DTC for the main body ECU using the Techstream.

      Refer to DTC CHECK / CLEAR

      Body Electrical > Body Control Module > Clear DTCs 

    4. Depress the brake pedal.
    5. Retrieve the main body ECU DTCs using the Techstream.

      Refer to DTC CHECK / CLEAR

      Body Electrical > Body Control Module > Trouble Codes 

    6. Is the same DTC displayed?

      Result

      Result
      Yes
      No

    Result:  2

    Yes 

    See step  19

    Result:  1

    No 

    See step  18

  18. VERIFY IF OTHER DTCS DISPLAYED 
    1. Are any other DTCs displayed?

      Result

      Result
      Yes
      No

    Result:  1

    Yes 

    REPAIR OR REPLACE THE MALFUNCTIONING PART ACCORDING TO THE APPLICABLE DTC TROUBLESHOOTING. 

    1. Refer to DIAGNOSTIC TROUBLE CODE CHART

    Result:  2

    No 

    DTC TROUBLESHOOTING COMPLETED. 

  19. REPEAT THE INSPECTION FROM STEP 1. 
    1. If the malfunction recurs, replace the main body ECU.

      Refer to REMOVAL

    2. Go to the next step.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  18

  20. REPLACE THE REAR COMBINATION LIGHT ASSEMBLY (RH), THEN GO TO THE NEXT STEP 
    1. Refer to REMOVAL

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  21. REPLACE THE REAR COMBINATION LIGHT ASSEMBLY (RH), THEN GO TO STEP 17. 
    1. Refer to REMOVAL

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  22. REPLACE THE REAR COMBINATION LIGHT ASSEMBLY (LH), THEN GO TO STEP 17. 
    1. Refer to REMOVAL

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  23. REPLACE THE REAR COMBINATION LIGHT ASSEMBLY (LH), THEN GO TO STEP 17. 
    1. Refer to REMOVAL

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  24. REPLACE THE HIGH MOUNTED STOP LIGHT ASSEMBLY, THEN GO TO THE NEXT STEP. 
    1. Refer to REMOVAL

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  13

  25. REPLACE THE HIGH MOUNTED STOP LIGHT ASSEMBLY, THEN GO TO STEP 17. 
    1. Refer to REMOVAL

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  26. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN THE FOLLOWING TERMINALS: 
    • Brake light (LH) terminal E37-3 - main body ECU terminal E1-30
    • Brake light (RH) terminal E38-3 - main body ECU terminal E1-30
    • High mounted stop light assembly terminal E46-2 - main body ECU terminal E1-30
    1. If there is a common connector:
      1. Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
      2. Repair or replace the malfunctioning part.
    2. If there is no common connector:

      Repair or replace the wiring harness which has an open circuit.

    3. Go to Step 17.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  27. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN THE FOLLOWING TERMINALS: 
    • Brake light (LH) terminal E37-3 - main body ECU terminal E1-30
    • Brake light (RH) terminal E38-3 - main body ECU terminal E1-30
    • High mounted stop light assembly terminal E46-2 - main body ECU terminal E1-30
    1. If there is a common connector:
      1. Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.
      2. Repair or replace the malfunctioning part.
    2. If there is no common connector:

      Repair or replace the wiring harness which has a short to power supply.

    3. Go to Step 17.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  28. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN THE FOLLOWING TERMINALS: 
    • Brake light (LH) terminal E37-3 - main body ECU terminal E1-30
    • Brake light (RH) terminal E38-3 - main body ECU terminal E1-30
    • High mounted stop light assembly terminal E46-2 - main body ECU terminal E1-30
    1. If there is a common connector:
      1. Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
      2. Repair or replace the malfunctioning part
    2. If there is no common connector:

      Repair or replace the wiring harness which has a short to ground.

    3. Go to Step 17.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  29. REPAIR OR REPLACE THE CONNECTOR, THEN GO TO STEP 17. 

    Result

    Proceed to
    NEXT

    Result:  1

    NEXT 

    See step  17

  30. REPAIR OR REPLACE THE CONNECTOR, THEN GO TO STEP 17. 

    Result

    Proceed to
    NEXT

    Result:  1

    NEXT 

    See step  17

  31. REPAIR OR REPLACE THE CONNECTOR, THEN GO TO STEP 17. 

    Result

    Proceed to
    NEXT

    Result:  1

    NEXT 

    See step  17

  32. REPAIR OR REPLACE THE CONNECTOR, THEN GO TO STEP 17. 

    Result

    Proceed to
    NEXT

    Result:  1

    NEXT 

    See step  17

  33. REPLACE THE BRAKE LIGHT BULB (RH), THEN GO TO STEP 17. 
    1. Refer to REPLACEMENT

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

  34. REPLACE THE BRAKE LIGHT BULB (LH), THEN GO TO STEP 17. 
    1. Refer to REPLACEMENT

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  17

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