HVAC control panel problems

[ethanmccll]

I’ve had to warranty my autozone hvac panel 4 times now because every other month something goes wrong on the replacement. Fan speed would stop working, ac on/off button would quit responding, blend door switch would get stuck on a certain setting. The factory 25 amp fuse for the ac is still in place. Would it be a good idea to replace it with a lower amp fuse to maybe mitigate whatever is going on? I’m not too good diagnosing electrical but I just want my truck to stop going through hvac panels. Any advice would be appreciated

 

[DerekTheGreat]

What year truck?

'88-'94 generally looked the same, with a recirc (Max) button being added later. At that same time, the reference voltage to the blend doors and such changed from something like 5 volts to 9. I don't remember exactly, but the point is that if you put a later style head unit in an older truck, it won't work for long. I've never tried putting an early head unit into a later truck, but I imagine similar things would happen. Can't say I'd trust Autozone electronics for anything. If I were you, I'd go to a "treasure yard" and find a replacement unit.

 

[ethanmccll]

What year truck?

'88-'94 generally looked the same, with a recirc (Max) button being added later. At that same time, the reference voltage to the blend doors and such changed from something like 5 volts to 9. I don't remember exactly, but the point is that if you put a later style head unit in an older truck, it won't work for long. I've never tried putting an early head unit into a later truck, but I imagine similar things would happen. Can't say I'd trust Autozone electronics for anything. If I were you, I'd go to a "treasure yard" and find a replacement unit.

1998

 

[someotherguy]

The newer style interior A/C controls have always seemed a far more fragile design to me, having a lot more problems than the early design. I wonder if it's just crap quality aftermarket parts you're dealing with? That's a lot of random failures that don't seem to point to any one cause other than suspect quality.

Richard

 

[PAIRA90S]

On my 90 GMC I found that the wire harness got stretched when I changed the stereo. In the center of the dash. It looked plugged in, but I checked it & hvac would work for a while(weeks to a month) then start losing functions. Snaked a tiny cable tie through the plug &it was fine (still is) for the last yr . It also happened on My 90Chevy. I guess I get a little aggressive when wiring the head unit.