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Home >> Infiniti >> 2008 >> QX56 AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P0327 To P1145 >> DTC P0643: Sensor Power Supply >> On Board Diagnosis Logic >> Notes
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On Board Diagnosis Logic: Notes

This self-diagnosis has the one trip detection logic. 

DTC DETECTING CONDITION CHART

DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0643
0643
Sensor power supply circuit short ECM detects a voltage of power source for sensor is excessively low or high.
  • Harness or connectors (APP sensor 1 circuit is shorted.)

    (PSP sensor circuit is shorted.)

    (Battery current sensor circuit is shorted.)

    (Refrigerant pressure sensor circuit is shorted.)

    (EVAP control system pressure sensor circuit is shorted.)

  • Accelerator pedal position sensor
  • Power steering pressure sensor
  • Refrigerant pressure sensor
  • EVAP control system pressure sensor