99 grand am climate control HELP!

[mars1]

99 [COLOR=green! important][COLOR=green! important]grand [COLOR=green! important]am[/color][/color][/color] se 3.4L 85,000 miles.



A/C is running when air flow control is set to floor or floor/vent with fan turned on even though ac power button is off.

However if air flow control is set to vent only I have to push ac power button on like normal to turn on ac.

If I turn fan off then the ac doesn't run anyway regardless of air flow direction- like normal.

Maybe related it seems also that regardless of air flow selection I always have some airflow coming out of vents

Could this all be climate control switch assembly/

[xeroinfinity]

Welcome to AF !

The AC will come on when you select the MAX setting which is all the way to the left. The AC button doesnt have to be pressed when it is in the Defrost setting either.

Have you checked the AC relayss ??

And it could be the HVAC head unit thats bad.

[mars1]

What you are saying is the way I understand it exactly.

However the way it is acting is as follows:

In max and defrost I have to push ac button on.

In bilevel and lower it is defaulting to high a/c signal and running without pushing ac button( What it should be doing in max and def.)

. And on upper (or normal ac mode) I also have to push ac button which is the only thing doing what it is supposed to do.

seems like something is reversed or the control assy is bad.