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92 bonneville ac relay

07-06-2004, 04:08 PM
The air conditioning in my bonneville does not work. The problem has been traced to be before the relay. When the ac is turned on the relay does not see a different voltage. Does anybody have the wiring diagram so I can tell what the wires run to. I would really appreciate it.

07-06-2004, 08:02 PM
Do you have the Electronic Climate Control or the manual knob type? Are you saying that the AC compressor is not kicking on when it should or is your problem the blower?

07-07-2004, 01:19 PM
The comperssor is not kicking in. My vehical has the knob controls.

07-07-2004, 09:22 PM
I can't post copywritten material on a forum but I'll try to get you started. PM me and maybe I can fax the wiring diagram to you.

There are two safety switches between the AC selector dial and the PCM. This is to prevent the compressor from coming on when the system is low on refrigerant or the system is over pressurized. Typically, this is the reason why most AC compressors do not cycle like they are supposed to. Once the PCM sees that everything is OK from the two sensors, it sends a ground output along a lt. green wire to the AC compressor relay. This in turn sends +12 volts supplied by fuse 5 in the relay center along a dk. green wire to the AC compressor clutch.

Personally, I would check the fuses involved and the relay for proper operation. If everything is fine there then I would head to a shop to have the AC system serviced. There is not too much the shadetree mechanic can do with the system as far as leak detection, pressure testing and/or refill.

If you still want the diagram and have access to a fax machine during the day then send a PM. The diagram will be for a 1993 but should be the same.

07-12-2004, 06:30 PM
I have checked the fuses and all are fine. I have been able to find a wire diagram and have chased the problem to be either in the wires leading to the relay, in the computer, or a combination.

07-12-2004, 07:00 PM
Test the wires at the 2 safety switches and then at the PCM both in and out. If all of this tests out correctly then test the terminal at the relay center, test the relay and the wire going into the compressor.

Just work down the line as the diagram shows.

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