Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read DTCs and record on the repair order.
2. With the scan tool, run a vehicle Scan Report, or record the Environmental Data related to the DTCs.
3. With the scan tool, erase all DTCs.
4. Using the recorded Environmental Data and the When Monitored Conditions above, operate the vehicle in the conditions that set the DTC.
5. With the scan tool, read Body Control Module (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 .
CHECK FOR VOLTAGE ON THE (F721) FUSED B(+) CIRCUIT
1. Turn the ignition off.
2. Disconnect the Switch Bank Module harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F721) Fused B(+) circuit at the Switch Bank Module harness connector.
  Is the voltage below 9.0 volts?
  
  Yes
  - Remove and inspect Fuse F31 (15A) for an open.
  - If Fuse Is Okay: Repair the open in the (F721) Fused B(+) circuit. Install Fuse F31 (15A).
  - If Fuse Is Open: Repair the short to ground in the (F721) Fused B(+) circuit. Replace Fuse F31 (15A).
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (Z932) GROUND CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Measure the resistance between ground and the (Z932) Ground circuit at the Switch Bank Module harness connector.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the open in the (Z932) Ground circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (D402) LIN BUS CIRCUIT FOR AN OPEN
1. Disconnect the BCM C6/F harness connector.
2. Measure the resistance of the (D402) LIN Bus circuit between the Switch Bank Module harness connector and the BCM C6/F harness connector.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the open in the (D402) LIN Bus circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK FOR VOLTAGE ON THE (D402) LIN BUS CIRCUIT
1. Reconnect the BCM C6/F harness connector.
2. Turn the ignition on.
3. Measure the voltage on the (D402) LIN Bus circuit in the Switch Bank Module harness connector.
  Is there any voltage present?
  
  Yes
  - Replace the Switch Bank Module in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 6
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.