2005 Ford Econoline E150, Van Cargo, 5.4 LFACTORY OEM SERVICE PROCEDURE

DTC P0122: Throttle Position (TP1) Sensor Circuit Low Input

P0122 - THROTTLE POSITION (TP1) SENSOR CIRCUIT LOW INPUT

For Vehicles With Electronic Throttle Control (ETC) 
Description:  The electronic throttle control (ETC) TP1 sensor was flagged as fault status by the powertrain control module (PCM) indicating a low voltage or open circuit.
Possible Causes: 
  • Open ETC TP sensor harness
  • Short to ground in the ETC TP sensor harness
  • Damaged TP sensor
  • SIG RTN circuit open to the TP sensor
Diagnostic Aids:  This fault exhibits a symptom of limited power. A TP1 PID (TP V PID) reading less than 3.42% (0.17 volt) in key on engine off (KOEO), continuous memory, or key on engine running (KOER) indicates a hard fault.
For All Others 
Description:  The 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). If during key on engine off (KOEO), or key on engine running (KOER) the TP rotation angle (or voltage) changes above the maximum calibrated limit, the test fails.
Possible Causes: 
  • TP sensor not seated properly
  • TP circuit open to PCM
  • VREF open to TP sensor
  • TP circuit short to GND
  • Damaged TP sensor
Diagnostic Aids:  This fault exhibits a symptom of limited power. A TP PID (TP V PID) reading less than 3.42% (0.17 volt) in key on engine off (KOEO), continuous memory or key on engine running (KOER) indicates a hard fault.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Vehicles With Electronic Throttle Control (ETC) GO to DV: Throttle Body Assembly ETC STEP DV1.
All others GO to DH: Throttle Position (TP) Sensor STEP DH12. GO to DH: Throttle Position (TP) Sensor STEP DH12. GO to DH: Throttle Position (TP) Sensor STEP DH11.
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