You remove the RDO/BATT fuse as specified. This will power down the HVAC control module. Some people have found that you have to remove this fuse with the key in the ON position and reinstall it to get the HVAC control module to run through its calibration phase.

 

OK thanks.

 

I'm still dealing with a crappy blend door problem. Keep in mind, I've got the auto fan function, and auto vent "output" select, with the degrees F selector... so I imagine it is the auto climate control thing. That's cool and all.

Figured out B+ is battery voltage... that's key info that I didn't know. Anyway, on the fuse box under the hood, its labeled B+, which indicates the wire from the battery. So I left the ignition in run and pulled the RDO/BATT fuse for 15 seconds or so. Reinserted it, watched the second hand for 40 sec, and turned the vehicle on. Still cycles.

Should the control panel be turned off, on, auto or anything in between for this process to work? When I get out there today I'll probably try a bunch of different settings to see if it works.

Thanks for the replies. Its a long hot drive from FL to NV.

 

If a rest did not work, even after trying it repeatedly, then the actuator is probably shot. The HVAC control module is supposed to read the number of step counts it takes to reach each limit. If it cannot properly read the steps, then it will not know when the door is open or closed. The most likely cause of this is a bad temp door actuator.

 

Indeed I tried it repeatedly. Here are the steps I took;

Ignition off, HVAC off, temp control to cold - Pulled fuse no luck.
Ignition to RUN, HVAC off, temp cont to cold - again.
Ignition off, HVAC on, temp cont to mid range - neg fix
Ignition on, HVAC on, temp cont to mid range - again, nothing.
Ignition on, HVAC on AUTO, temp to cold.... and no good.
Engine Running, HVAC on and off, temp to mid range - no dice!

So, suffice to say I think Kyle is right. If I'm not mistaken, its behind the glove box, which I was able to reach in with my hand. I didn't feel any vibrations from mechanical movement while back there while the car was running, though the air was cycling hot to cold.
Is this part able to be changed from behind the glove box? Or is this going to require removing most of the dash?

*Answered my question: Kyle had a post here about the whole procedure:
https://blazerforum.com/forum/showth...+door+actuator

 

Oldie but goodie. I should move that into the Tech Article (DIY) section sometime...