Diagnostic Test

READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN
1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. With the scan tool, run a Vehicle Scan Report or record the Environmental Data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for at least 10.0 seconds.
5. Turn the ignition on.
6. Using the recorded Environmental Data and the When Monitored Conditions, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.
Did the DTC return?

Yes
- Go To 2
No
- Perform the TESTING FOR AN INTERMITTENT CONDITION diagnostic procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
PERFORM THE APPROPRIATE HVAC ACTUATOR CALIBRATION / AUTO ADDRESSING ROUTINE TEST AND CHECK FOR THE DTC TO RETURN
NOTE:
NO HVAC mode or temp functions will perform as desired unless auto-addressing was successful.

NOTE:
Auto-addressing needs to be done every time the HVAC Module or an HVAC Actuator is replaced.

NOTE:
Diagnose and repair all LIN Bus related DTC's before performing this test procedure.

With the scan tool, perform the appropriate HVAC Actuator Calibration/Auto Addressing Routine and recheck DTCs.

Did any of the above test routines fail?

Yes
- Replace the faulty component that failed the HVAC Actuator Calibration/Auto Addressing Routine and or LIN issue in Accordance with the Service Information.
- Perform the HVAC VERIFICATION TEST. Refer to HVAC VERIFICATION TEST .
No
- Perform the TESTING FOR AN INTERMITTENT CONDITION procedure, if DTC is still present proceed to step 3. Refer to TESTING FOR AN INTERMITTENT CONDITION .
ISOLATE AND CHECK THE RECIRCULATION DOOR CONTROL SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. The ignition must be off when checking a circuit for continuity to ground.
2. Isolate the circuit by disconnecting the Electronic Control Unit (HVAC) and the component harness connectors containing the circuit being tested. Note: Use the wiring diagram as a guide to follow the path of the circuit. Check the disconnected connectors and related harnesses for damage, corrosion, and loose fitting terminals.
3. Connect the negative lead of the Digital Volt-Ohm Meter (DVOM) to a known good ground.
4. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.
NOTE:
When back-probing a circuit at a harness connector, always use an appropriate back probing tool to prevent damage to the connector terminals.

Is there continuity between ground and the circuit being tested?

Yes
- Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and identify any in-line connectors that may help isolate the location of the short.
- Perform the HVAC VERIFICATION TEST. Refer to HVAC VERIFICATION TEST .
No
- Go To 4
ISOLATE AND CHECK THE RECIRCULATION DOOR CONTROL SIGNAL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT AT THE HVAC HARNESS CONNECTOR
1. The ignition must be off when performing a resistance check to find a short between circuits.
2. Isolate the circuit by disconnecting the Heating Ventilation Air Conditioning Module (HVAC) and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note: Use the wiring diagram as a guide to follow the path of the circuit.
3. Connect one lead of the DVOM to the circuit being tested at the HVAC harness connector.
4. With the other lead of the DVOM probe all other circuits at the HVAC harness connector.
NOTE:
With the circuit isolated there should be no continuity between the circuit being tested and any other circuit.

Is there continuity between the circuit being tested and any other circuit?

Yes
- Repair the short between the circuits that have continuity. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors to help isolate the location of the short.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
No
- Go To 5
REPLACE THE RECIRCULATION DOOR ACTUATOR AND CHECK FOR THE DTC TO RETURN
1. Replace the Recirculation Door Actuator in accordance with the Service Information. Refer to ACTUATOR, RECIRCULATION DOOR, REMOVAL AND INSTALLATION .
2. Connect the Recirculation Door Actuator, HVAC, and any other disconnected harness connectors.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Using the Environmental Data and When Monitored conditions, 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
- Replacing the Recirculation Door Actuator corrected the condition.
- Perform the HVAC VERIFICATION TEST. Refer to HVAC VERIFICATION TEST .
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 .