DTC P0647-00: A/C Compressor Magnetic Clutch Control System: High Input

P0647-00: (PCM - VIN Y) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	A/C compressor magnetic clutch control system: High input
Detection condition	The A/C compressor magnetic clutch control voltage is the standard or more relative to the PCM control signal.
Fail-safe	Release the magnetic clutch.
Possible cause	A/C relay malfunction (Refer to RELAY INSPECTION in the service information.) Malfunction in wiring harness (including connector/terminal) between A/C relay and PCM (see CIRCUIT INSPECTION .) (see CONNECTOR INSPECTION .) PCM malfunction (Refer to applicable PCM REMOVAL/INSTALLATION (VIN Y) in the service information.)
Repeatability verification procedure	Clear the DTC recorded in the memory. (see CLEARING DTC .) Set the A/C temperature control to MAX COLD. Turn the A/C switch on to operate the air conditioner. Verify that cold air is flowing from the air vent. Perform the DTC inspection for the PCM. (See DTC INSPECTION .)
Courtesy of MAZDA MOTORS CORP.
1	Battery
2	IG1 relay
3	A/C relay
4	PCM