P0645
Air Conditioning Clutch Relay Circuit Malfunction
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0645 means
- The fault code P0645 signifies that there is a problem with the circuit responsible for controlling the A/C clutch relay. This may cause issues with the A/C system operation.
Possible symptoms
- Inoperative A/C system
- Illuminated check engine light
- Poor A/C system performance
Possible causes
- Failed A/C clutch relay
- Shorted or open wiring or connections in the circuit
- Corroded or loose electrical connections
- Failed engine control module (ECM)
Related parts
- AC Clutch Relay: The A/C clutch runs the A/C compressor. Problems lead to reduced or no AC cooling
Possible solutions
- Replace the A/C clutch relay
- Check for and repair any damaged wiring or connections
- Clean or tighten any loose or corroded electrical connections
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0645 on OBD DashX
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