: 1986 RWD fleetwood

06-23-10, 07:51 AM
I just got this 1986 caddy. Most receiver dryers I'm used to had a pressure switch on it for cycling the the compressor on/off. This one doesn't. somebody wired it to constantly run once the air is selected on. So my high side is about 100 psi and the low side goes from 58 down to 5PSI. The compressor has the two wires brown and blue going to it with the crossover diode. In the wire loom leading to the compressor a thrid black wire came out and went to chassi ground. The anti-freeze switch {has the capillary tube} has the black & brown wires which the brown goes to the compressor. My major question, Isn't there suppose to be a pressure switch on the accumulator/dryer? If so also could you possible post a wiring diagram for the ac system, cause I know I'm gonna have to do reconstructed surgery on the car. tia (My mitchell chassie manual for an 1985 didn't help nor did the mitchell AC manual for a 1991. I can't find a caddy electrical/vacumm manual anywheres including ebay.)

06-23-10, 07:08 PM
The pressure switch is on the back of the compressor.


Also note the low pressure switch is grounded and the blue line is one solid wire. The switch is open below 20 PSI and closed above 30.