2003 GMC Sierra 1500HD with dual zone automatic climate control:
I recently had the classic clunking noise from one of the door actuators on my 2003 Sierra. I accessed the driver’s side blend air door and mode actuators. Both appeared to work fine. I removed the dash, braces, passenger air bag, and OnStar box to gain access. By this time the multiple clunking sound was gone and replaced by a single clunk as the refresh door swung to full refresh. I was able to thoroughly troubleshoot all the door actuators by running them through all settings. The only one that didn’t work properly was the refresh door. At start up, it cycled smoothly from refresh to recirc, then back to refresh. However, it will not go to recirc position when pressing the recirc button on the control panel. I decided to replace both the passenger blend air door and recirc door actuators while I had everything torn apart. No change in operation. I have done several manual re-calibrations of the door motors (HVAC system), which did not change anything. I decided to reinstall everything but the dash cover and peripherals. Now the refresh door no longer cycles at all, either at start up or by command. Also, the manual re-calibration of the system no longer works. Any help would be appreciated.
I recently had the classic clunking noise from one of the door actuators on my 2003 Sierra. I accessed the driver’s side blend air door and mode actuators. Both appeared to work fine. I removed the dash, braces, passenger air bag, and OnStar box to gain access. By this time the multiple clunking sound was gone and replaced by a single clunk as the refresh door swung to full refresh. I was able to thoroughly troubleshoot all the door actuators by running them through all settings. The only one that didn’t work properly was the refresh door. At start up, it cycled smoothly from refresh to recirc, then back to refresh. However, it will not go to recirc position when pressing the recirc button on the control panel. I decided to replace both the passenger blend air door and recirc door actuators while I had everything torn apart. No change in operation. I have done several manual re-calibrations of the door motors (HVAC system), which did not change anything. I decided to reinstall everything but the dash cover and peripherals. Now the refresh door no longer cycles at all, either at start up or by command. Also, the manual re-calibration of the system no longer works. Any help would be appreciated.