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Home >> Infiniti >> 2021 >> QX80 Premium Select, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTCS) (4 Of 5) >> Engine (ECM) >> DTC P2123: App Sensor >> DTC Description >> DTC Detection Logic
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DTC Detection Logic

NOTE: If DTC P2122 or P2123 is displayed with DTC P0643, perform the trouble diagnosis for DTC P0643. Refer to DTC Description .

DTC No.

Trouble diagnosis name

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P2122

APP SEN 1/CIRC

(Accelerator pedal position sensor 1 circuit low input)

An excessively low voltage from the APP sensor 1 is sent to ECM.

  • Harness or connectors

    (APP sensor 1 circuit is open or shorted.)

  • Accelerator pedal position sensor

    (APP sensor 1)

P2123

APP SEN 1/CIRC

(Accelerator pedal position sensor 1 circuit high input)

An excessively high voltage from the APP sensor 1 is sent to ECM.