OK, I have had this problem before and have searched the forum for answers. I have tried to clear this message, I have tried filling the system with the 134a as required. I cannot get the compressor to switch on and I have tried to by pass the pressure switch. I am out of ideas, what have I missed? I was able to get past this last year, I thought!:confused:

How much freon did you put in? Might need to evac. and recharge to make sure freon level is correct. Try clearing any codes the car has stored.

Your car uses R12, not R134a........... unless it has been converted.

I thought 1993 and earlier vehicles used R12, No?

MIne is posted 134a right on the drier. Don't think it was ever converted, looks to be originl GM tag.

I have also truied to clear the codes but the message will not clear. I have heard it may require me to disconnect battery, i this correct? Can't you just use the on-board system? Of course thatdoesn't seem to b working for me!

I have the same problem with my 1990 Seville. I just got it filled with R-12 and the message still comes on even after clearing computer codes & disconnecting the battery. If you disconnect battery, you may be able to use the A/C and then the "Low AC Refrigerent" message will come on for about 2 weeks until the Compressor finally shuts off. I've had this message for the 5 years I've owned the car. My Freon R-12 level is 40% Pressure which the mechanic told me is the correct amount. The same amount is in there that was put in 2 weeks ago. Nothing leaked out. He even said my AC looked like it was in good condition. There is definitely a Ghost In The Machine.

Well, I thought that the switch over from R12 to R134a was '96.

If you guys are clearing the codes correctly, and the system is verified full with no leaks, then perhaps you have a bad low pressure switch or a poor connection to it.

Well, I got through this last night. The code for the "very low refrigerant" is in the APC list and each seperate list, PCM, APC, TPC etc must be cleared individuall, which now I know. Once I cleared this the compressor came on and I could add the refridgerant no problem, Cold A/C again! THanks for the help!:thumbsup:

MIne is posted 134a right on the drier. Don't think it was ever converted, looks to be originl GM tag.

Just for the record my 94 STS has the same sticker .134A

dboncio99,

I thought you only had to clear the error codes that flash at the beginning of diagnostics. Are you saying to go into each setting in APC and clear codes ? I'm confused. Mmmmm...

Dino

Correct