DTC P0123: Throttle/Pedal Position Sensor A Circuit High

2010 Mercury Mariner Premier, 2.5 7, FWDSECTION DTC P0123: Throttle/Pedal Position Sensor A Circuit High
DTC P0123: THROTTLE/PEDAL POSITION SENSOR A CIRCUIT HIGH

For Vehicles With An Idle Air Control (IAC) Valve 
Description:  The throttle position (TP) sensor circuit is monitored by the powertrain control module (PCM) for a high TP rotation angle (or voltage) input through the comprehensive component monitor (CCM). The test fails if the TP rotation angle (or voltage) changes above the maximum calibrated limit.
Possible Causes: 
  • TP sensor not seated correctly
  • TP sensor harness short to voltage
  • TP sensor harness short to VREF
  • SIG RTN circuit open to the TP sensor
  • Damaged TP sensor
Diagnostic Aids:  A TP PID reading greater than 93% (4.65 volts) in ignition ON, engine OFF or ignition ON, engine running indicates a concern is present.
For All Others 
Description:  The electronic throttle control (ETC) throttle position (TP) sensor 1 circuit was flagged as a concern by the powertrain control module (PCM) indicating a high voltage.
Possible Causes: 
  • TP sensor harness short to voltage
  • TP sensor harness short to VREF
  • ETCRTN circuit open
  • Damaged TP sensor
Diagnostic Aids:  This concern exhibits a symptom of limited power. A TP1 PID reading greater than 4.75 volts in ignition ON, engine OFF or ignition ON, engine running indicates a concern is present.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Ranger GO to PINPOINT TEST DH .
All others GO to PINPOINT TEST DV .
RENDER: 1.0x

NO RELATED

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