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DTC U0142-68: Lost Communication With Body Control Module "B" Event Information: Procedure

  1. VERIFY 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. Switch the ignition ON (engine off or on) and wait for 5 s or more.
    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
      Yes
      No

    Result:  2

    No 

    See step  9

    Result:  1

    Yes 

    See step  2

  2. INSPECT POWER MANAGEMENT CONTROL ECU CONNECTOR CONDITION 
    1. Switch the ignition off.
    2. Disconnect the negative battery cable.

      Refer to REMOVAL

    3. Disconnect the power management control ECU 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  16

    Result:  1

    Yes 

    See step  3

  3. 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  15

    Result:  1

    Yes 

    See step  4

  4. INSPECT POWER MANAGEMENT CONTROL ECU CIRCUIT FOR SHORT TO GROUND 
    1. Verify that the power management control ECU and main body ECU connectors are disconnected.
    2. Inspect for continuity between main body ECU terminal E1-13 (wiring harness-side) and body ground.
    3. Is there continuity?

      Result

      Result
      Yes
      No

    Result:  2

    Yes 

    See step  14

    Result:  1

    No 

    See step  5

  5. INSPECT POWER MANAGEMENT CONTROL ECU CIRCUIT FOR SHORT TO POWER SUPPLY 
    1. Verify that the power management control ECU 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 E1-13 (wiring harness-side).
    5. Is the voltage 0 V?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  13

    Result:  1

    Yes 

    See step  6

  6. INSPECT POWER MANAGEMENT CONTROL ECU CIRCUIT FOR OPEN CIRCUIT 
    1. Switch the ignition off.
    2. Disconnect the negative battery cable.

      Refer to REMOVAL

    3. Verify that the power management control ECU and main body ECU connectors are disconnected.
    4. Inspect the wiring harness for continuity between power management control ECU terminal E3-15 (wiring harness-side) and main body ECU terminal E1-13 (wiring harness-side).
    5. Is there continuity?

      Result

      Result
      Yes
      No

    Result:  2

    No 

    See step  12

    Result:  1

    Yes 

    See step  7

  7. VERIFY IF MALFUNCTIONING LOCATION IS POWER MANAGEMENT CONTROL ECU DEPENDING ON REPEATABILITY 
    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. Switch the ignition ON (engine off or on) and wait for 5 s or more.
    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:  1

    Yes 

    See step  11

    Result:  2

    No 

    See step  9

  8. 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. Switch the ignition ON (engine off or on) and wait for 5 s or more.
    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  10

    Result:  1

    No 

    See step  9

  9. 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. 

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

      Refer to INSTALLATION

    2. Go to the next step.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  9

  11. REPLACE THE POWER MANAGEMENT CONTROL ECU, THEN GO TO THE NEXT STEP. 
    1. Refer to INSTALLATION

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  8

  12. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN POWER SOURCE CONTROL (POWER MANAGEMENT CONTROL ECU) TERMINAL E3-15 AND MAIN BODY ECU TERMINAL E1-13. 
    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 8.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  8

  13. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN POWER MANAGEMENT CONTROL ECU TERMINAL E3-15 AND MAIN BODY ECU TERMINAL E1-13. 
    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 8.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  8

  14. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN POWER MANAGEMENT CONTROL ECU TERMINAL E3-15 AND MAIN BODY ECU TERMINAL E1-13. 
    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 8.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  8

  15. REPAIR OR REPLACE THE CONNECTOR, THEN GO TO STEP 8. 

    Result

    Proceed to
    NEXT

    Result:  1

    NEXT 

    See step  8

  16. REPAIR OR REPLACE THE CONNECTOR, THEN GO TO STEP 8. 

    Result

    Proceed to
    NEXT

    Result:  1

    NEXT 

    See step  8

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