Why are AC compressors grounded?
A “grounded compressor” or “compressor short to ground” means that an electrical winding inside the compressor has broken and hit the side of the compressor. This causes a direct short to ground, igniting the oil and causing a burnout. And, of course, the circuit breaker trips due to the sudden current surge.
What causes compressor to short to ground?
When a compressor has a short-to-ground, it is likely caused by damage to the insulation within the compressor itself. Damage to the insulation is likely caused by acid within the system. Acid in the system can result from improper system evacuation or the presence of air/moisture in the system.
What does it mean when my compressor is grounded?
This means that one of the electrical windings inside the compressor has broken. When this happens the winding will hit the side of the compressor causing a direct short to ground. Usually this will ignite the oil causing a burnout.
What to do if your AC compressor relay is not grounding?
But before splashing $100 on a replacement PCM you better be DARM sure the relay control ground wire is making contact with the above mentioned pin on the PCM. You can always use a meter to check if the PCM is working. Just connect one probe of the meter to the battery positive voltage and the other to pin 27 of the PCM.
What should I do if my compressor clutch is not working?
If you’re not getting battery voltage, pull the compressor clutch relay and check for power and ground on the relay control coil terminals in the socket. Wiring varies by make, model, and year. Some car makers trigger the relay control coil ground through the PCM or ECM.
What causes an AC compressor to not engage?
If the clutch doesn’t engage, the problem could be a blown fuse, an open in the wire to the clutch coil, a bad clutch coil, a poor ground, or a low pressure lockout. AC compressor clutches receive power in a number of ways. They can activate through a relay that’s energized directly by a proper condition of the low and high pressure switches.