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
  - Perform the appropriate INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK FOR VOLTAGE ON THE (F982) FUSED IGNITION SWITCH OUTPUT (RUN/ACC) CIRCUIT
1. Turn the ignition off.
2. Disconnect the Interior Rearview Mirror harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F982) Fused Ignition Switch Output (RUN/ACC) circuit at the Interior Rearview Mirror harness connector.
  Is the voltage below 9.0 volts?
  
  Yes
  - Remove and inspect Fuse F77 (10A) for an open.
  - If Fuse Is Okay: Repair the open in the (F982) Fused Ignition Switch (RUN/ACC) circuit. Install Fuse F77 (10A).
  - If Fuse Is Open: Repair the short to ground in the (F982) Fused Ignition Switch (RUN/ACC) circuit. Replace Fuse F77 (10A).
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (Z912) GROUND CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Measure the resistance between ground and the (Z912) Ground circuit at the Interior Rearview Mirror harness connector.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the open in the (Z912) Ground circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK FOR VOLTAGE ON THE (D402) LIN BUS 2 CIRCUIT
1. Turn the ignition on.
2. Measure the voltage on the (D402) LIN Bus 2 circuit at the Interior Rearview Mirror harness connector.
  Is there any voltage present?
  
  Yes
  - Replace the Interior Rearview Mirror in accordance with the Service Information. Refer to MIRROR, REARVIEW, REMOVAL AND INSTALLATION .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK THE (D402) LIN BUS 2 CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the BCM C7/G harness connector.
3. Measure the resistance of the (D402) LIN Bus 2 circuit between the Interior Rearview Mirror harness connector and the BCM C7/G harness connector.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the open in the (D402) LIN Bus 2 circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 6
CHECK RELATED MODULE 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. Connect all BCM 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
  - 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.