AC problem, 92 Bonneville

"Alpha One" wrote: > The AC in my 92 Bonneville is not cooling at all. The clutch > does not > engage. Fuses OK, fan working. The pressure is well into the > red on the low > pressure side, > but the compressor in not working of course. About a month ago > I charged the > system after I let it finish emptying completely with R-124a > which it was > using before. It was leaking through the valve, I replaced it. > Any idea what > it may be? > Thank you. > > Tony

Could be a lot of things, when you open a the system to replace valve, did you vacum the system down before you recharged it? Also have you checked the the low pressure cut out switch to on recv/dryer? I assume it was a R12 system that you converted over or was it native R134? And finally, a pressure reading in the red on the low side is meaningless when the system is not running.

It was changed to R-124a a few years ago by an AC shop. I, about a month ago, only let more gas escape to almost empty and refiled it.

I checked three switches including the low pressure one and I think they should be either open or closed. I tested both states on each and it does not cause the clutch to engage. I am not sure if this is a way of testing them.

If I apply a voltage directly to the clutch it will engage and the AC works, cooling the car.

I wonder if it is the thermostatic switch. How can I access it? Thank yopu,

T> > The AC in my 92 Bonneville is not cooling at all. The clutch

Could be a ground problem, use a test light to verify voltage is reaching clutch, and that ground is good. Or, run a fused jumper direct to clutch, if clutch clicks, problem in wiring / switch No click = bad clutch