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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read Body Control Module (BCM) DTCs and record on the repair order.
    2. Record the Environmental Data and any DTCs.
    3. With the scan tool, erase DTCs.
    4. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    5. With the scan tool, read BCM DTCs.

      Did the DTC return?

      Yes 

      • Go To  2

      No 

      • Test complete. The condition or conditions that originally set this DTC are not present at this time. Using the appropriate SYSTEM WIRING DIAGRAMS as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  2. CHECK THE REAR WINDOW DEFOGGER RELAY FOR PROPER OPERATION 
    1. Turn the ignition off.
    2. Remove the Rear Window Defogger Relay from the Power Distribution Center (PDC) Assembly.
      NOTE:

      If the substituted relay does not change the DTC status to Stored, reinstall the relay that was previously removed.

    3. Temporarily substitute the relay with a known good relay.
    4. Turn the ignition on.
    5. With the scan tool, erase DTCs.
    6. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    7. With the scan tool, read BCM DTCs.

      Did the DTC return?

      Yes 

      • Go to  3

      No 

      • Replace the Rear Window Defogger Relay.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  3. CHECK THE (C115) DEFOGGER RELAY CONTROL CIRCUIT FOR CONTINUITY TO GROUND 
    1. Turn the ignition off.
    2. Remove the Rear Window Defogger Relay from the PDC Assembly.
    3. Check for continuity between ground and the (C115) Defogger Relay Control circuit at the Rear Window Defogger Relay terminal in the PDC Assembly.

      Is there continuity between ground and the (C115) Defogger Relay Control circuit?

      Yes 

      • Go To  4

      No 

      • Go To  6
  4. CHECK THE PDC ASSEMBLY FOR AN INTERNAL SHORT 
    1. Disconnect the PDC Assembly C2 harness connector.
    2. Check for continuity between ground and the (C115) Defogger Relay Control circuit at the PDC Assembly C2 harness connector.

      Is there continuity between ground and the (C115) Defogger Relay Control circuit?

      Yes 

      • Go To  5

      No 

      • Go To  8
  5. CHECK THE (C115) DEFOGGER RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND 
    1. Disconnect the BCM C6 harness connector.
    2. Check for continuity between ground and the (C115) Defogger Relay Control circuit at the BCM C6 harness connector.

      Is there continuity between ground and the (C115) Defogger Relay Control circuit?

      Yes 

      • Repair the short to ground on the (C115) Defogger Relay Control circuit.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Go To  9
  6. CHECK THE (C115) DEFOGGER RELAY CONTROL CIRCUIT FOR AN OPEN 
    1. Turn the ignition off.
    2. Remove the Rear Window Defogger Relay from the PDC Assembly.
    3. Disconnect the BCM C6 harness connector.
    4. Measure the resistance of the (C115) Defogger Relay Control circuit between the BCM C6 harness connector and the Rear Window Defogger Relay terminal in the PDC Assembly.

      Is the resistance above 3.0 Ohms?

      Yes 

      • Go To  7

      No 

      • Go To  9
  7. CHECK THE PDC ASSEMBLY FOR AN INTERNAL OPEN 
    1. Disconnect the PDC Assembly C2 harness connector.
    2. Measure the resistance of the (C115) Defogger Relay Control circuit between the PDC Assembly C2 and the BCM C6 harness connector.

      Is the resistance above 3.0 Ohms?

      Yes 

      • Repair the open in the (C115) Defogger Relay Control circuit.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Go To  8
  8. CHECK RELATED PDC ASSEMBLY HARNESS CONNECTIONS 
    1. Disconnect all PDC Assembly harness connectors.
    2. Disconnect all related in-line harness connections (if equipped).
    3. Disconnect the related component harness connectors.
    4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
      • Proper connector installation.
      • Damaged connector locks.
      • Corrosion.
      • Other signs of water intrusion.
      • Weather seal damage (if equipped).
      • Bent terminals.
      • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
      • Terminals that have been pushed back into the connector cavity.
      • Perform a terminal drag test on each connector terminal to verify proper terminal tension.

      Repair any conditions that are found.

    5. Connect all PDC Assembly harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. With the scan tool, erase DTCs.
    9. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    10. With the scan tool, read BCM DTCs.

      Did the DTC return?

      Yes 

      No 

  9. CHECK RELATED BCM HARNESS CONNECTIONS 
    1. Disconnect all BCM harness connectors.
    2. Disconnect all related in-line harness connections (if equipped).
    3. Disconnect the related component harness connectors.
    4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
      • Proper connector installation.
      • Damaged connector locks.
      • Corrosion.
      • Other signs of water intrusion.
      • Weather seal damage (if equipped).
      • Bent terminals.
      • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
      • Terminals that have been pushed back into the connector cavity.
      • Perform a terminal drag test on each connector terminal to verify proper terminal tension.

      Repair any conditions that are found.

    5. Reconnect all BCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    7. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. With the scan tool, erase DTCs.
    9. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    10. With the scan tool, read BCM DTCs.

      Did the DTC return?

      Yes 

      No 

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