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Home >> Mazda >> 2007 >> CX-9 Touring, 3.5 C, AWD >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System MZI-3.5) >> DTC P0645 >> Notes
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DTC P0645: Notes

DTC P0645 (MZI-3.5) DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0645 A/C relay control circuit
DETECTION CONDITION 
  • Monitors the A/C relay control circuit output from the PCM. The test fails when the PCM grounds the A/C relay control circuit, excessive current draw is detected on the A/C relay control circuit; or, with the A/C relay control circuit not grounded by the PCM, voltage is not detected on the A/C relay control circuit (the PCM expects to detect vehicle power voltage coming through the A/C relay coil to the A/C circuit).
POSSIBLE CAUSE 
  • A/C relay malfunction
  • Connector or terminal malfunction
  • Open circuit in wiring between main relay terminal No.1 D and A/C relay terminal A
  • Open circuit in wiring between A/C relay terminal E and PCM terminal 1N
  • Short to ground in wiring between A/C relay terminal E and PCM terminal 1 N
  • Short to power supply between A/C relay terminal E and PCM terminal 1 N
G04969300Courtesy of MAZDA MOTORS CORP.