Diagnostic Test

CHECK FOR ACTIVE BUS COMMUNICATION DTCS
NOTE:
Make sure the Ignition Off Draw (IOD) fuse is installed and the battery is fully charged before proceeding.
1. Turn the ignition on.
2. With the scan tool, read DTCs.
  Are any Active BUS Communication DTCs set?
  
  Yes
  - Refer to DIAGNOSIS AND TESTING and perform the Stored Lost Communication DTCs diagnostic procedure.
  No
  - Go To 2
CHECK FOR STORED BUS COMMUNICATION DTCS
1. Turn the ignition on.
2. With the scan tool, read DTCs.
  Are any inactive or stored BUS Communication DTCs set?
  
  Yes
  - Refer to DIAGNOSIS AND TESTING and perform the Stored Lost Communication DTCs diagnostic procedure.
  No
  - Go To 3
CHECK FOR POWERTRAIN CONTROL MODULE (PCM) A/C COMPRESSOR DTCS
1. Turn the ignition on.
2. With the scan tool, read PCM DTCs.
  Are any PCM A/C Compressor DTCs set?
  
  Yes
  - Refer to DIAGNOSTIC CODE INDEX and perform the appropriate diagnostic procedure.
  - Perform the HVAC VERIFICATION TEST. Refer to HVAC VERIFICATION TEST .
  No
  - Go To 4
CHECK FOR BODY CONTROL MODULE (BCM) DTCS
1. With the scan tool, read BCM DTCs.
  Are any DTCs set in the BCM?
  
  Yes
  - Refer to DIAGNOSIS AND TESTING and perform the Stored Lost Communication DTCs diagnostic procedure.
  No
  - Go To 5
CHECK THE A/C COMPRESSOR
1. Ignition on, engine running.
2. Using the HVAC Module, request A/C maximum cool.
  Does the A/C Compressor Clutch engage?
  
  Yes
  - Go To 6
  No
  - Refer to COMPRESSOR, A/C, DIAGNOSIS AND TESTING .
CHECK IF THE DTC RESETS
1. Turn the ignition off.
2. Turn the ignition on.
3. With the scan tool, erase DTCs.
4. Turn the ignition off.
5. Turn the ignition on.
6. With the scan tool, perform the A/C Cool-down Test. Follow the instructions on the scan tool.
7. With the scan tool, read HVAC DTCs.
  Does this DTC reset?
  
  Yes
  - Go To 7
  No
  - Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all HVAC Module 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 HVAC Module 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 HVAC Module DTCs.
  Did the DTC return?
  
  Yes
  - Replace the HVAC Module in accordance with the Service information. Refer to MODULE, HVAC, REMOVAL AND INSTALLATION .
  - Perform the HVAC VERIFICATION TEST. Refer to HVAC VERIFICATION TEST .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the HVAC VERIFICATION TEST. Refer to HVAC VERIFICATION TEST .