TrailBlazer 4WD L6-4.2L VIN S (2002)
10. Verify that no DTCs have set as current DTCs.
Primary HVAC
When replacing the HVAC control module it will be necessary to allow the HVAC control module to perform a re-calibration process. When installing
the HVAC control module be sure to perform the following:
1. Place the ignition switch to the OFF position.
2. Disconnect the scan tool.
3. Install the HVAC control module.
4. Re-connect all previously disconnected components.
5. Place the ignition switch in the RUN position.
6. Wait 40 seconds for the HVAC control module to re-calibrate.
7. Verify that no DTCs have set as current DTCs.
When replacing the motor assembly it will be necessary to allow the HVAC control module to perform a re-calibration process. When installing the
motor assembly be sure to perform one of the following:
Preferred Method (W/ Scan Tool)
1. Clear all DTCs
2. Place the ignition switch in the OFF position.
3. Install the motor assembly.
4. Re-connect all previously disconnected components.
5. Place the ignition switch in the RUN position.
6. With the scan tool, initiate the Motor Re-calibration feature of the HVAC module Special Functions menu.
7. Verify that no DTCs have set as current DTCs.
Alternate Method (W/O Scan Tool)
1. Clear all DTCs
2. Place the ignition switch to the OFF position.
3. Disconnect the scan tool.
4. Install the motor assembly.
5. Re-connect all previously disconnected components.
6. Remove the HVAC B fuse for a minimum of 10 seconds.
7. Re-install the HVAC B fuse.
8. Place the ignition switch in the RUN position.
9. Wait 40 seconds for the HVAC control module to re-calibrate.
10. Verify that no DTCs have set as current DTCs.
Recirculation Actuator
REMOVAL PROCEDURE
1. Remove the HVAC module assembly.
2. Remove the air inlet assembly.
3. Remove the screws from the air inlet assembly.
4. Remove the recirculation actuator screws.
5. Remove the recirculation actuator.
INSTALLATION PROCEDURE
