Diagnostic Test

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
  - Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer TESTING FOR AN INTERMITTENT CONDITION to STANDARD PROCEDURE .
CHECK THE (Z341) GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Left Tail/Liftgate Lamp Assembly harness connector.
3. Measure the resistance on the (Z341) Ground circuit between ground and the Left Tail/Liftgate Lamp Assembly harness connector.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the open or high resistance on the (Z341) Ground circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE LEFT REAR TURN LAMP BCM OUTPUT
1. Turn the ignition on.
2. Turn the Left Turn Lamps on.
  NOTE:
  The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
3. Connect a 12-volt test light between the (Z341) Ground circuit and the (L163) Left Rear Stop/Turn Signal Feed circuit at the Left Tail/Liftgate Lamp Assembly harness connector.
  Does the test light illuminate brightly in sequence with the Left Turn Lamps?
  
  Yes
  - Replace the Left Tail/Liftgate Lamp Assembly in accordance with the Service Information. Refer to LAMP, TAIL, REMOVAL AND INSTALLATION .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (L163) LEFT REAR STOP/TURN SIGNAL FEED CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the BCM C3/C harness connector.
3. Measure the resistance on the (L163) Left Rear Stop/Turn Signal Feed circuit between the Left Front Lamp Assembly harness connector and BCM C3/C harness connector - terminal 6.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the open circuit or high resistance in the (L163) Left Rear Stop/Turn Signal Feed circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK RELATED 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
  - Replace the Body Control Module (BCM) in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL AND INSTALLATION .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  - Test complete.