1988 Chevy Celebrity AC Electrical Problem

Tiny
AASPARKCHASER
  • MEMBER
  • 1988 CHEVROLET CELEBRITY
  • 6 CYL
  • FWD
  • AUTOMATIC
  • 261,000 MILES
The AC on my 1988 Chevrolet Celebrity quit working so I had it converted to R-134 and charged up. The compressor still won't run unless a jumper wire is used. The owner's manual lists an AC relay. Could that be the problem? Or the control on the dash?
Do you
have the same problem?
Yes
No
Thursday, August 19th, 2010 AT 8:16 PM

8 Replies

Tiny
WRENCHTECH
  • EXPERT
Or fuses or pressure switches or wiring, or ECM etc, etc

The circuit needs to be systematically checked with a wiring diagram to determine what the problem is.
Was this
answer
helpful?
Yes
No
-1
Thursday, August 19th, 2010 AT 9:07 PM
Tiny
AASPARKCHASER
  • MEMBER
Thanks for the schematic. I have checked the fuses. They were both okay. Time to dig out the mulitmeter.
Was this
answer
helpful?
Yes
No
Thursday, August 19th, 2010 AT 10:01 PM
Tiny
AASPARKCHASER
  • MEMBER
Multimeter. They should have spell check on this forum.
Was this
answer
helpful?
Yes
No
Thursday, August 19th, 2010 AT 10:03 PM
Tiny
WRENCHTECH
  • EXPERT
You can use a paper clip to jump out the switch plugs to determine if they are the problem.
Was this
answer
helpful?
Yes
No
Friday, August 20th, 2010 AT 4:22 AM
Tiny
AASPARKCHASER
  • MEMBER
Unfortunately, the block diagram does not show me the location of the various components. There are what appear to be two pressure switches on the high pressure line coming out of the compressor. One has voltage to it and one does not. Even if I install a jumper on the one that has voltage I do not get voltage at the other. From what I can see on the block diagram, the current travels through the low pressure switch and then through the high pressure switch to the ECM and then to ground. It also travels through the compressor clutch relay to the compressor clutch.

There are three relays near the right front fender behind the grille. Is one of those the compressor clutch relay and if so, which one?
Was this
answer
helpful?
Yes
No
Wednesday, September 15th, 2010 AT 2:34 AM
Tiny
WRENCHTECH
  • EXPERT
Yes, one of them is the A/C relay but the way you verify that is with wire colors. Originally it was the one on the end toward the center of the car but it could have been moved by now.
Was this
answer
helpful?
Yes
No
+1
Wednesday, September 15th, 2010 AT 4:28 AM
Tiny
AASPARKCHASER
  • MEMBER
Am I correct in assuming those two connectors on the high pressure line coming out of the compressor and going upward vertically are connected to the low and high pressure switches? Or are the pressure switches located elsewhere? I did notice later that there appeared to be a connector to the compressor itself. Some of my co-workers have stated that sometimes the high pressure switch is located right on the compressor.
Was this
answer
helpful?
Yes
No
Wednesday, September 15th, 2010 AT 5:22 PM
Tiny
WRENCHTECH
  • EXPERT
You can identify the switch by which line it is in. The low pressure switch will be in the low pressure side, usually right on the accumulator. If you have a switch in the compressor, that will be the high pressure switch. Again, use the wire colors to be sure.
Was this
answer
helpful?
Yes
No
Wednesday, September 15th, 2010 AT 5:27 PM

Please login or register to post a reply.

Recommended Guides