Thanks for any who reply!

I have a 97 TC LXI. Have taken it into the shop to see why the AC doesn't work. Shop says it's the climate control switch. So I replaced it with a used one a few months ago. AC Button lights up, but compressor never engages. Same as the original switch.

I have disconnected the connector at the compressor. I have ground on the black wire, but nothing on the blue wire. This leads me to think the shop is correct.

Before I go and get a new control unit from the dealer (not cheap), I have a few questions:

1) How likely is it that it is just the switch and not something between the switch and the compressor?
2) Can I jumper the compressor to at least see if it does engage and does blow out cold air for 5 minutes? Would I just put 12v+ to the blue wire?
3) Can I jumper anything at the switch to try and engage the compressor? Either at the wiring harness or on the board itself? Would rather do it at the harness then at the board though.

Freon levels are good accoring to the shop.

I did have the main computer replaced last fall with a brand new unit from the dealer. By computer I mean the main one that keeps track of what you have on the car, milage, etc. Not a cheap part. I'm wondering if AC was forgot when it was programmed. I can't remember when it worked the last time cause my wife used to drive it.

 

Anyone have any suggestions?

 

Things i would check:
[ol][*]Test the low pressure switch. if defective, compressor will not engage. very easy and cheap to replace[*]Test the level of refrigerant[*]Connect 12v to the compressor clutch wire with the engine OFF and see if it clicks. If it clicks I would take off the belt and see that after I put a charge to that wire that it actually engages the clutch by trying to turn it by hand. you could just add power to the wire with the engine running but my suggestion is safer for both you and the AC system.[/ol]
-Jerry

 

Thanks Jerry. Few followup questions

Where is the low pressure switch? Any suggestions on how to replace it?
For testing the compressor, it has 2 wires going to it, I know the black has ground, so should I just put power to the blue wire? or do I need to complete the circuit? I'm used to doing this test with single wire compressors where it gets it's ground from the engine.

I'm told the refridgerant levels are good, so have to believe that at the moment cause I only have a low pressure gauge.

 

From a post elsewhere:

The '98 shop manual pictures it to be in the liquid-side refrigerant line, attached to a T-fitting in the line that is located very close to the alternator drive pulley. It is not very large, so just follow the line until you come upon it. The wire colors are violet/white, dark blue, and black/light blue. The wires are attached to pins 61, 42, and 43 of the powertrain controller, respectively, so you can check that out. If you replace the transducer also replace the o-ring.

For installation, you may want to by the repair book at the auto parts store or event better, invest in a Factory Service Manual or for a reasonable fee, join www.alldatadiy.com

Best to run the black to ground but probably not needed. I would just because it's there.

One other thing to check is to open the relay panel under the hood and swap the relay for the ac with any other one to see if it might just be a relay problem. the relays are generally the same for various other items on the van and they should just plug and unplug into the board the same way.

good luck...

-Jerry

 

Thanks. Thought the relay, and fuse, so I replaced them both with known good ones.

it's funny, this is the only car I have owned where I didn't have a shop manual or even the haynes manual on. Will test the compressor in a few hours and track down the low pressure switch.

thanks again and have a great weekend.

 

Ok. I have gone ahead and put 12v+ and ground to the compressor and it engages.

I have also traced the wire from the compressor to inside the car and it seems to go somewhere under the drivers side foot well, but cant trace it to the switch. Any thoughts? Is there anything up around the steering column that also controls the AC switch?

 

How about the low pressure switch? found and tested? if we have the proper refrigerant, and the proper amount, and a clutch that engages, but no signal to tell it to do so, I am inclined to check the low pressure switch.

-Jerry