Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. With a scan tool, select read DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
VERIFY THAT THE BODY CONTROL MODULE IS CAPABLE OF SETTING AMBIENT AIR TEMPERATURE (AAT) SENSOR FAULTS
1. Check the BCM fault code list to verify that the BCM has the capability to set DTCs against the AAT Sensor. Refer to BODY CONTROL MODULE (BCM) - DIAGNOSTIC CODE INDEX .
  Are there any AAT Sensor faults listed in the DTC list for the BCM?
  
  Yes
  - Go To 3
  No
  - Go To 4
CHECK THE BODY CONTROL MODULE FOR AAT SENSOR FAULTS
1. With the scan tool, read DTCs in the BCM.
  Is the BCM setting any DTCs against the AAT Sensor?
  
  Yes
  - Perform the diagnostic procedure in the BCM. Refer to BODY CONTROL MODULE (BCM) - DIAGNOSTIC CODE INDEX .
  No
  - Replace and program the Body Control Module in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL .
CHECK THE AAT SENSOR WIRING AND CONNECTORS FOR DAMAGE OR POOR FIT
1. Turn the ignition off.
2. Disconnect the AAT Sensor harness connector.
3. Disconnect the appropriate BCM harness connector.
4. Check the AAT Sensor wires:
  - for an open condition.
  - for a short to voltage.
  - for a short to ground.
  - for a short to each other.
  Were any problems found with the wiring?
  
  Yes
  - Perform the appropriate repair of the wiring.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
REPLACE THE AAT SENSOR AND CHECK DTCS
1. Replace the AAT Sensor in accordance with the Service Information.
2. Connect the AAT Sensor and PCM harness connectors.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Using the Freeze Frame Data or When Monitored Conditions above, operate the vehicle within the conditions that set the DTC.
6. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Go To 6
  No
  - Replace the Ambient Air Temperature (AAT) Sensor in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
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.
  - Check for spread terminals and 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. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace the BCM in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .