Common Symptoms
- Air conditioning does not engage or cycle properly
- A/C compressor runs continuously without cycling off
- Check Engine Light or Service Engine Soon light illuminated
- A/C system blows warm air intermittently
- No A/C compressor clutch engagement sound when A/C is activated
Most Likely Root Causes
- Shorted A/C clutch relay or relay control circuit
- Damaged or shorted wiring harness to A/C compressor clutch relay
- Failed PCM/ECM internal relay driver circuit
- Corroded or damaged relay socket connections
- Short to voltage in relay control wire
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Component Location
The A/C clutch relay is typically located in the underhood fuse and relay box, usually on the driver side fenderwell or near the battery.
Manufacturer Notes
Some vehicles may set this code if aftermarket accessories create voltage feedback into the A/C relay control circuit.
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