FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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General Information





P0646 A/C Clutch Relay Control Circuit Low

General Information

Component Location





General Description

The A/C relay is activated if the A/C switch is ON while the blower is running and system operation is enabled the PCM. Power is then supplied to the A/C compressor electromagnetic clutch and A/C system is operated. The A/C compressor is switched out to prevent it running when full engine output is required or there is a risk of overheating. The PCM also inhibits compressor operation on starting to permit running conditions to stabilize.

DTC Description

If there is Short to ground in A/C control relay control circuit, PCM sets DTC P0646.

DTC Detecting Condition





Schematic Diagram