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Q: when I turn the ignition switch to on, the ac compressor clutch will engaged. Disconnected the ac control switch and still

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When I turn the ignition switch to on, the ac compressor clutch will engaged. I disconnected the power to the air conditioning control but still does the same thing. Do I have a faulty ignition switch?

My car has 91000 miles.
My car has an automatic transmission.

A: On some earlier years of Chevy they used to...

On some earlier years of Chevy they used to have the A/C compressor to come on when you are turning off the engine to help the prevent the engine from suffering from excessive after-run conditions that the engine will continue to run even though the car is switched off. This is on for about a 5 second timer after the key is turned off.

If you are having the A/C compressor stay on when the engine is running even though you have the A/C or defrost off, then you have probably have a problem with the A/C compressor relay is sticking on or is shorted causing the compressor to stay on. I recommend having the system checked by a mechanic like one from YourMechanic to diagnose the system for you and replace your A/C compressor relay if necessary.

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