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92 gmc Sububran A/C clutch

I have a 1992 GMC Suburban with an A/C problem.



The clutch does not work correctly. It does not turn when the A/C button is pushed.



I unplugged the wire harness and jumped it from the battery , the clutch kicks on.



So I know the clutch is OK.



Is there sensor somewhere that it bad, does any one have a wire diagram for the A/C system thanks.

The AC system may be low on refrigerant charge. If it is, there’s a low pressure switch in the system that prevents the compressor clutch from engaging so the compressor isn’t damage from the low refrigerant charge.

Tester

Like Tester said, this is most likely due to a loss of refrigerant. There’s a surefire way to check if the clutch is operating.

Locate the receiver/drier (silver cylinder mounted on the passenger side firewall). There should be a two-wire plug hooked to this. Unhook the connector, short the contacts on the connector together (a paper clip works well), and turn the A/C on. The clutch should engage and operate the compressor.

If this works, then you are low on refrigerant and have a leak somewhere.

You probably need a system recharge. Since you have a '92 model you need to get it retrofitted to R134a.

On a orfice tube system (like GM uses) the silver bottle thingy is called a accumulator. You can jump the switch as advised.