Anyone here have an A/C system wiring guide for a '91 Continental? My A/C compressor only likes to work sometimes, not always. If I switch between say Floor/Auto rapidly sometimes it will come on, but as soon as the car is shut off its a gamble wether its gonna come on again. I even tried jumpering the low pressure switch, but nothing. I was thinking of putting a switch inside that activated the compressor and the fan so I could run it manually.
A/C Problem
- Thread starter WackyWRZ
- Start date
Frankie X
New member
First question: does the cooling fan come on when A/C is commanded?
If yes, try a simple experiment. While the engine is running and the A/C is on, use a long screwdriver to push the clutch plate toward the pulley. FS-6 and FX-15 compressors wear the clutch surfaces, the air gap becomes too large, and the field can't pull the disc in. If the clutch engages when you try this, the clutch disc has to be reshimmed so the gap between it and the pulley is .018-.030". Try to stay on the narrow side.
If yes, try a simple experiment. While the engine is running and the A/C is on, use a long screwdriver to push the clutch plate toward the pulley. FS-6 and FX-15 compressors wear the clutch surfaces, the air gap becomes too large, and the field can't pull the disc in. If the clutch engages when you try this, the clutch disc has to be reshimmed so the gap between it and the pulley is .018-.030". Try to stay on the narrow side.
Frankie X
New member
Continuing on, if it's electrical:
1. The control head sends 12v. to the Green/Orange wire at the cycling switch when A/C is on. Is it there? If not, the problem is in the head or wiring from it.
2. This 12v. leaves the closed switch via the Purple wire and goes to the "Integrated Relay Control Module" (that's the black box on top of your rad. It controls A/C and cooling fan, among other things). Still got 12v there? If not, trace the wire for an open.
3. Check for powers to the IRCM. 2 Black/Orange, a Brown, and a Yellow will be hot at all times. A Red/Green will be hot in run. If not, check fuses L,G, or F in the underhood fuse box or open wiring. Everything good there?
4. Check output from the IRCM. Disconnect the clutch and check for 12v. across the 2 wires at the clutch connector. If no, and the wires between there and the IRCM are OK, replace IRCM. If yes, the clutch field is NFG.
One other thing- the PCM cuts the compressor out at 90% throttle. Are you having any TPS problems (false WOT)? Is your Check Engine light on?
Hope this helps!
1. The control head sends 12v. to the Green/Orange wire at the cycling switch when A/C is on. Is it there? If not, the problem is in the head or wiring from it.
2. This 12v. leaves the closed switch via the Purple wire and goes to the "Integrated Relay Control Module" (that's the black box on top of your rad. It controls A/C and cooling fan, among other things). Still got 12v there? If not, trace the wire for an open.
3. Check for powers to the IRCM. 2 Black/Orange, a Brown, and a Yellow will be hot at all times. A Red/Green will be hot in run. If not, check fuses L,G, or F in the underhood fuse box or open wiring. Everything good there?
4. Check output from the IRCM. Disconnect the clutch and check for 12v. across the 2 wires at the clutch connector. If no, and the wires between there and the IRCM are OK, replace IRCM. If yes, the clutch field is NFG.
One other thing- the PCM cuts the compressor out at 90% throttle. Are you having any TPS problems (false WOT)? Is your Check Engine light on?
Hope this helps!