My car does have the temp switches. One on each side of the orifice connector. I will give this a try. Thanks for the info. Will post the results.

 

I'll add my 2 cents. What amount of freon is listed on the yellow freon decal under hood? is it exactly 2 lb.? if so, then level is fine, if not then its either over or undercharged, which could be the whole problem. With the factory manual you can verify A/C pressure readings, both hi and low thru the DIC. The manual will confirm whether the system is reading correctly ruling out or confirming a faulty sensor. Every time my DIC reading states to service the A/C I get a F code which I erase. My system will only set this code when outside temp is approx. what my temp display is set to. I know my car is about 3 ounces low on R12 so its working as designed. The clutch is allowed to operate not by letting voltage reach the clutch but by a completed ground circuit. The ECU and BCM open and close grounds to provide power to components or to turn off components. To procede logically, you need the factory manual to confirm pressure readings and if they are not in spec the manual will tell you where to check next. This era of GM cars, Allante included, had an "orfice tube" that if partially plugged up with debris would raise pressures within the system and disable the ground circuit to the compressor clutch until that orfice was replaced, freon full or not. I find the Allante to be the best early warning system of any GM car of that era. 99.9% of the time the messages, codes are correct.You make reference to the "Cadillac book" do you mean the factory manual? Bottom line, without the factory manual either you or the A/C technician will get frustrated and throw parts at this car.

 

Yes I was refering to the factory manual. For some reason, I can't find the decal that tells me the proper fill level and such. As previously stated, I don't get any codes and strangely, I get this error message whether thesystem ison or not! Another odd thing Carnut, I notice that when the system does stay on for a minute or two, the air blows coldest when it switches back to Econ, go figure. Not constantly but for a few seconds, it is ice cold air coming out of the vents.

 

Also, the orifice was changed prior to my taking possesion of the car. It was replaced and the system was supposed to be vacuumed and recharged by the dealer. This was in May, had it vacuumed and recharged in June when a small leak was detected at the low pressure fill. Still to no avail.

 

How is the quicky lube getting hi and low pressure readings if the compressor kicks off? Why was the orfice changed? debris? The proper freon amount is listed in the FSM. I'm missing something here. If a worded message displays a code will set, Pressures are not monitored inOFF setting, but could be in ECON.

 

list year and model in your profile next to the 96 DeVille.

 

Not sure I know what you mean but its a 1996 Deville base model. It will run for a few minutes sometimes. The book says 2.0 lbs, which is what they filled to and what registers as full at recheck. And I know, thats whats strange to me. When the system is OFF, it will give me the error message. However, when I do the diag check (off and warm button) all categories say NO CODES. Not sure why the orifice was changed, but I saw it when they took it out, it was dirty. Didn't see it when they replaced it, just trusting that they did put in a new one.

 

Sorry for the mistake. I toggle back and forth between 3 Cad sites, thought is was an Allante!

 

Thanks for the tip. I think I finally got it! Stays on and blows pretty cool air. I didn't know you had to vacuum the system prior to changing these switches so I lost some refrigerant. But I think I have it back right. I may just go and have it vacuumed and refilled to be sure. But right now its blowing pretty good. Got my thermometer out and it got down to almost 40 degrees while wide open. I think that's pretty good, don't you? I'll keep you guys posted on the performance.

 

By the way, the temp switch was $33.87 + tax from the Cadillac dealer. FYI