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Home >> Infiniti >> 2012 >> QX56 RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P1550 To P2A03 >> DTC P2127, P2128: App Sensor >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

DTC No. Trouble diagnosis name (Trouble diagnosis content) DTC detecting condition Possible cause
P2127 APP SEN 2/CIRC
(Accelerator pedal position sensor 2 circuit low input)
An excessively low voltage from the APP sensor 2 is sent to ECM.
  • Harness or connectors

    (Accelerator pedal position sensor 2 circuit is open or shorted.)

    (Battery current sensor circuit is shorted.)

    [Camshaft position sensor (bank 1) circuit is shorted.]

    (Crankshaft position sensor circuit is shorted.)

    (Refrigerant pressure sensor circuit is shorted.)

    (EVAP control system pressure sensor circuit is shorted.)

  • Accelerator pedal position sensor (APP sensor 2)
  • Battery current sensor
  • Camshaft position sensor (bank 1)
  • Crankshaft position sensor
  • Refrigerant pressure sensor
  • EVAP control system pressure sensor
P2128 APP SEN 2/CIRC
(Accelerator pedal position sensor 2 circuit high input)
An excessively high voltage from the APP sensor 2 is sent to ECM.