Climate Control System Question

[80redcoupe]

Team,

As I work through the "opportunities" with my 81 Coupe... I have an issue that seemed odd, but I am not sure.

When I start the car, the Climate control comes on. I can shut it off and all stays off until I shut the car down and restart. Even if the system is off when car is shut down, as soon as the car is started again.... It's back on.

Should that be happening?

[TJ Hopland]

What do you mean by 'on'?   The digital display?   The blower?   It is normal when the ignition is on and you have off selected that the blower still runs on low.    With the ignition off the blower and display should both be off.

Digital climate control was only on some models in 80 so 81 is still fairly early.  Most common failure always was the blower control module.  Not sure if with age there are going to be some new ones or not.   Blower control module usually fails so the blower just doesn't work at all but I have seen them fail so the blower is stuck on full blast any time the battery is connected.   The blower control module is like the resistor module on lesser cars and is mounted near the blower motor on the air duct.   

[80redcoupe]

TJ,

Thank you for jumping in on this.

The system turns on. Display comes on and blows when car is turned on.

Here is an example:

Get in the car, turn the key on. start the car.... Climate control comes on (display) and fan blows. I can adjust fan speed and temperature so I believe the blower control module is fine. I can turn the system off. I then shut the car off, and when key is turned back on/restart the car the climate control and blower is back on. In other words... I dont HAVE to turn it on.

Seems odd...

[TJ Hopland]

Ahh,  you are asking if its normal for it to not remember what mode it was in last time it was on.   I think I always had it on on my 80 so may not have noticed if it defaulted to auto.   I could see them thinking that would be a good way to do it but I could also see what ever memory circuit it has failing with age.   Does the radio memory work?  Or isn't it a stock radio?   I'm just thinking that maybe they used the same power circuit for both the radio and climate control memory and if one doesn't work that could be a clue that there is a blown fuse or something along those lines.   

I do have an 80 electrical manual and the full 81 service manual but not sure where either one is at the moment.  I'm not sure if either of those would describe how that is supposed to work or not. 

[80redcoupe]

Yeah.... That is my question TJ.

I will look at my Electrical manual for common power source.