P0647: Air Conditioning Clutch Relay Control Circuit High
What to do
Driveable, with air conditioning that does not cool. The refrigerant system is probably fine.
What this code means
The air conditioning clutch relay circuit is reading high — an open, or a control wire on a supply voltage. The compressor will not engage, so the air conditioning blows ambient air.
Likely causes
Start here
- Broken wire in control circuit · moderate
- Failed air conditioning clutch relay · easy
- Corroded or loose connector · easy
Less common
- Failed compressor clutch coil · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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