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Q: AC blows warm air, refrigerant was recharged.

asked by on

refrigerant was recharged. Still blows hot or warm air.

My car has 167000 miles.
My car has an automatic transmission.

A: Hi there. When the refrigerant was recharg...

Hi there. When the refrigerant was recharged, was the system evacuated and a vacuum test performed to ensure there are no leaks or moisture in the system? It sounds like the AC compressor may not be engaging. A blown fuse, relay, failed clutch, failed compressor, wire harness failure, or module could be the cause.

Attach a known good set of AC pressure gauges and monitor the high and low side pressures. If the pressures are about the same on both sides, then the compressor’s internal check valve has failed and is preventing the compressor from performing.

Make sure the AC indicator lights up when you turn on the AC. If it flashes, this is an indicator that the compressor is not coming on when commanded. The clutch, a relay, a fuse, or wire harness could be at fault. Check for blown fuses and relays that are not responsive when the AC is turned on and replace as necessary.

The AC clutch is an electromagnetic device that locks the ac pulley to the compressor to drive the compressor. If the clutch has failed or any of the electrical components that provide it power fail, then the clutch will not engage.

A quick voltage and ground check at the clutch and resistance check of the clutch will reveal any faults that may be present. If you would like to have this issue taken care of, a certified professional from YourMechanic can inspect your AC system and advise you on the appropriate repairs.

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