P1122 — Lincoln — Throttle Position TP Sensor Circuit Intermittent Low Voltage

P1122 (Lincoln): Throttle Position TP Sensor Circuit Intermittent Low Voltage — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Throttle Position TP Sensor Circuit Intermittent Low Voltage. Source catalogue definition; confirm applicability using vehicle service information.

Affected system: Powertrain

Symptoms

  • Check Engine light illumination
  • Erratic engine idle speed
  • Hesitation or stumbling during acceleration
  • Engine stalling at low speeds
  • Reduced overall engine power

Possible causes

  • Faulty Throttle Position (TP) sensor
  • Intermittent short circuit in the TP sensor signal wire
  • Damaged or corroded TP sensor electrical connector
  • Faulty throttle body assembly
  • Loose or frayed wiring harness leading to the TP sensor
  • Engine Control Module (ECM) communication error

What to check

  • Inspect the electrical connector at the throttle body for signs of corrosion or moisture
  • Test the TP sensor signal voltage using a multimeter to detect intermittent drops
  • Check the wiring harness for continuity and signs of chaffing between the sensor and ECM
  • Perform a throttle position sensor sweep test using a scan tool to monitor signal consistency
  • Verify proper throttle plate movement and clean any carbon buildup from the housing