2017-10-10
Inoperative A/C system
Illuminated check engine light
Poor A/C system performance
Failed A/C clutch relay
Shorted or open wiring or connections in the circuit
Corroded or loose electrical connections
Failed engine control module (ECM)
AC Clutch Relay: The A/C clutch runs the A/C compressor. Problems lead to reduced or no AC cooling
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
See which problems come with P0645, how often it shows up in other vehicles, and how to fix it — step by step. Free on OBD DashX, in 10 languages.
See P0645 on OBD DashX