DTC P0646-00: A/C Compressor Magnetic Clutch Circuit Low Input: Outline

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DTC P0646:00 (PCM, SKYACTIV-G) DETECTION CONDITION AND POSSIBLE CAUSE


System malfunction location	A/C compressor magnetic clutch circuit low input
Detection condition	The A/C compressor magnetic clutch control voltage at the PCM terminal 2AF is low for a continuous 5 s relative to the PCM control signal.
Fail-safe	Release the magnetic clutch.
Possible cause	A/C relay malfunction F47 15 A fuse malfunction Short to ground in A/C relay power supply circuit Open circuit in A/C relay power supply circuit Short to ground in A/C relay control circuit PCM connector or terminals malfunction PCM malfunction
Courtesy of MAZDA MOTORS CORP.