Sorry for the delayed response. The answer is NO. Several months ago the heater core went out. After seeing what a PITA is is to R&R I took it to a shop recently now that its in the single digits where they replaced the heater core and the 3 control motors with GM parts. Now I have only hot air all the time coming from the defrost and if the blower is on 5 the air output is probably half what it should be.
We then suspected the control module which was swapped with a used unit. It seemed it functioned somewhat for a minute then crapped out back to the same. I question the used junk yard module anyhow. After doing some more digging I found a U tube vid on silverado defroster stuck on. Its some 30+ mins long but has some good info. In short the mechanic tested the system and wiring best as possible considering GM's lack of tech data to trouble shoot and found the drive motor for the floor/dash/ defrost not moving. The system is run off 0 to 5V., 2.5 is the dash IIRC, 5 the defrost and 0 the floor.
For lack of a better explanation the motor drove past its 5v limit voltage to where the feedback to the module basically didn't know what to do and no longer responded to inputs. I saw this personally on the electronic equipment used to test. The way the HVAC box is made the foam on the blend doors stops the drivers below or at the max 5V output voltage. With the foam gone the flap or door and motor traveled past that point, the feedback exceeded 5V and the module went out of bounds. Instead of the drive motor having a stop, the blend door is used to stop the drive motor.
The mech removed the bottom left side drive motor and put a screw in the slot to stop the motor from exceeding the previous travel point. This kept the feed back signal to the module below 5V, and everything then worked as it should. Bottom line...more garbage engineering from GM and China made OEM drivers and parts. I know everyone here is pro GM, thats what we have GM's which is all I've ever owned more less for 45 years. Never again after this piece crap of an excuse for American made or "like a rock" yes, straight to the bottom of the sea is where todays Chevies should be.
For the how are chevies these days here is what failed between mine and a friends.
Transmissions, Oil pump O ring, heater controls, dash/speedo/gauge cluster, Transfer case rub issue, Intake gaskets, power seat motors, window motors, ebrake system self destructing, broken exterior door handles, leaking windshield gasket. Then we still have the piston slap and failing lifters that will never get fixed by me at least. I sold my square body years ago to "upgrade", Im still kicking myself in the ass.
