A/C question
 

Having a cab, I really never use A/C. But I still would like it to work in the event I need it.

Turning the A/C knobs all the way to the right won't turn on the A/C. I checked the 12V line into the compressor and it's not live.

If I put 12V to it by attaching to a nearby 12V source, then the compressor clicks on and I get cool air inside.

So my question is....What wires do I hunt to make the compressor turn on from inside the cabin?

Thanks in advance for your posts!

If your car has a low pressure cut-off switch, and is low on R12 (or r134), the compressor won't kick on until you recharge the a/c system. Look at the hoses leading to the compressor and check to see if one has a switch on it.

If you don't have a cut-off switch, then you should check for 12 volts on the input and output sides of the a/c switch inside the car. Pull the switch out, and put a voltmeter on it. If no 12 volt output, then the switch is bad. If you have 12 volts on the output side, then there's a problem with the wiring back to the compressor. Though I've never done it, it would seem to me that it shouldn't be too difficult to run a wire from the switch back to the engine bay, if need be.

Good luck, and let us know what you find.

Blown fuse? Check the fuses under the front hood.

LeRoux