Where is the A/C crompressor clutch relay - 1992 GMC Sierra

The compressor has a clutch, the clutch engages to a rotating pulley by the use of a clutch. The clutch is an electric solenoid, or plunger.
This clutch, or solenoid clutch gets 12 volts from the controls. From a thermostat, thru refrigerant pressure switch, thru coolant temperature switch, thru ambient temperature switch, fuses and control switch.
Where is the ac magnetic relay? i think it's the clutch you are refering to.

Have you replaced the relay? If it is not a bad relay, it sounds like you are pulling too many amps thru the relay. I would look for either a bad wire between the relay and the compressor clutch, a bad connection at either end (either at the relay or at the compressor clutch) or a bad clutch.

Most of the time there in the under hood fuse / relay box . an the clutch relay I'm assuming you mean the A/C compressor clutch relay . I mite be able to say for sure if I new what make, model an year vehicle .

If the Freon is low then the a/c clutch will not cut on.There should be a fuse box under the hood and the relay will be in it.

Refrigerant may have leaked out to a level compressor will not come on ck levels w guages

Have you tired jumping the AC compressor low pressure switch?

The relay is under a black plastic cover on the driver's side behind the battery. There are a couple other relays under there.-------I would start by jumping the AC relay to see if the clutch will run, you do this by removing the relay and putting a jumper wire between 30 and 87 terminals, if the clutch runs then check to see if there is power on the 85 terminal at the relay and a ground at terminal 86 if all are good replace the relay. The terminal numbers are located on the bottom of the relay, be sure that terminal 30 has power if the clutch does not run.
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Faulty compressor clutch relay. Check to see if the relay is receiving voltage when the A/C is turned on. Also check the relay wiring and ground connections. If bypassing the relay with a jumper wire or routing battery voltage directly to the compressor clutch makes the A/C work, the relay is probably bad.
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This will solve the problem or point you towards the cause of problem. Thank you for using fixya.

Since you know that the clutch must engage in order for the compressor to operate, then there are most likely one of causes. The first is low or no freon in the system. The a/c system has a pressure sensor mounted in the low( return) side hose that prevents the clutch to engage if the freon is too low. The second would be the a/c fuse or relay faulty, preventing the clutch solenoid( a 12 volt electrically operated solenoid) from engaging. And the third would be that the clutch itself is bad because the solenoid wiring has broken. I suggest that first you locate the a/c clutch relay in the relay panel, remove the relay, carefully remove the plastic cover from the relay and reinstall the relay. The clutch should engage the compressor when you manually close the relay contact with your finger for one or two seconds. If the clutch does engage, your electrical circuit in ok and you are probably low on freon. A half of a can of r-134 in more that enough to operate the pressure switch. If it doesn't engage, check the a/c fuse or the clutch solenoid itself. Get back to me and let me know how things went. Dano

Chances are it's your fan clutch or your relay to your fan clutch going bad, you can try swapping out your DRL relay with your fan clutch relay. There the same relay which is a actually more then a relay, it's more like a voltage regulator relay. The other suggestion is to have the dealer scan your Bravada for any related cooling DTC codes and see if there is a PCM upgrade program to address your issue.
http://forums.trailvoy.com/showthread.php?t=19604
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The starter relay is energized by the ignition switch, through either the neutral safety switch, or the clutch safety switch.