QuestionI have a 2002 Buick Regal. The A/C only starts at times. Sometimes after 1/2 hour it will come on. Very sporadic. I had the heater control assy. replaced but it only worked for a week and then went back to working intermittently. Can you help? Thanks.
AnswerJim,
You just threw me for a loop. You had the heater control assembly replaced, and it worked perfectly all the time every time... for a week? That leads me to three possible conclusions.
The first being of course that the control head that you had the old one replaced with also went bad. Was it a new part or a used part?
The second, is the plugs in the back of the control head may be making a bad connection somewhere. This makes sense to me because it worked after having it replaced, because there was tension on the plug from where it was pushed on. Now that it has had time to vibrate around withthe vehicle moving, perhaps it has loosened up and is making connection when it wants to.
The third is that it was just a coincidence that it worked right after having it replaced, and the mechanics mis-diagnosed the problem. How long ago was this done, and have you talked to them since about what it is doing?
In any case here are the first things that I would've asked you to check if you hadn't told me you had the control head replaced.
1. Any loose connections. Start with the Compressor wiring, and most importantly the compressor ground. Make sure the ground wire is tight and the connection point is free of corrosion. Then work your way from there to your high pressure switch, low pressure switch, make sure your a/c clutch relay is locked in the socket. Everything should be tight.
2. Your A/C clutch relay. Unplug it from the socket. Does it looked discolored at all on different spots? It may have the contacts inside "chattering" and breaking connection. Here is a quick check. Identify the coil contacts on the relay itself. If there is a diagram on the side of it, it is the contacts that are connected by what looks like a spring. Hook a jumper wire to the positive side of the battery and connect it to the connector on one side of the coil. Run another jumper wire from the negative side of the battery and touch it to the other coil connector. Do you hear or feel a slight "click"? Does it "click" and stay that way until you disconnect it? If it does, go ahead and plug it back in, it is good. If it doesn't replace the relay, the coil or contacts themselves are going / gone bad
I hope I was of a little help. If I can do more, let me know. If you found this helpful, please remember to rate this answer. Thank you for the question, and good luck in everything
