AC controls on Malibu 1999 and 2001

I have a 2 malibu’s a 99 and a 2001 with the same prob.

The AC controls seem to have a mind of their own. When I push the AC button it comes on but seems to go on and off at will and it seems to respond to different blower speeds and air circulation controls

Sometimes it will stabilize and stay on and somtimes it just flakes in and out


You don’t give enough details to say any thing other than a general "Your HVAC system needs to be diagnosed by a technican"or for me to just make a list of possibilites.

Could be the control head,could be the wires between the controlhead, could be a refridgerant issue, could be a system issue. You don’t say if these are "automatic or dual zone systems.

My WAG is that it is the control heads,simply because I have replaced dozens of them, but this is not the proper way to determine if a part has failed.

Same problem here as well on my 2002 Malibu. Sometimes AC works fine, other times AC light flickers on and off on certain fan speeds. On other fan speeds it works fine. Its not just the light, AC stops working with the light goes out too. No decernable pattern in the light flicker pattern, behaves like a short.

Had the extended warranty on it until last summer by which time I had the AC control head (where the fan and temp controls are) replaced at least 4 times (on my car with 65,000 miles). It fixed it each time but within a year or so, the problem typically comes back. I’ve noticed starting again now.

Anyone know if this is just a poor design of the control head or could this be an indicator of root cause elsewhere?

Its definitely the AC control head. I figured out a trick. You can gently wiggle the fan speed knob around the number you have selected until you get the AC light to stay on.