I just reinstalled the entire air conditioning system in my 99 nbs silverado single cab. Everything works great but the lower temperature blend actuator for the temp control (manual controls) was missing so I had to buy another. My question is what do I have to do to calibrate the actuator. I was told I have to do it but cant find the procedure on here. I have a snap on scanner at our shop if thats what I need. Please help me out if you know by chance so I dont have to contact the local GM dealer and wait on the phone wasting my time and theirs. Thanks in advance.

 

Anyone? Paleeez?

 

The GM service manual does not show any calibration procedure when replacing any of the HVAC actuators for the 99 model year, but I did find the procedure for a 2001 it should be the same. I would suggest installing the actuator and plugging in the electrical connector, then with the key off remove the HVAC 1 fuse from fuse box in the cab (left hand side at the end of the instrument panel) for 60 seconds. Then reinstall the fuse and turn the ignition on for 60 seconds without touching any of the HVAC controls.

 

Thank you 04. My dad called the local GM dealer and spoke to a fella in the shop and thats exactly what he said. Thank you for responding. Very helpful

 

Sorry to bring back an old post, but did the calibration method above work for you? I put a new actuator in and it moves very slow (not the sweeping movement I was imagining). It turns a little, stops, turns a little more, stops again, and so on until it gets to what it thinks is the end. I don't think it is closing the blend door completely, I have warm air but not hot. The pull the fuse method didn't work for me and am trying to figure out other ways. Hopefully the part I just got isn't defective. Thanks for your help.