P1125 — Nissan — Tandem Throttle Position Sensor Circuit Fault

P1125 (Nissan): Tandem Throttle Position Sensor Circuit Fault — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Tandem Throttle Position Sensor Circuit Fault. Source catalogue definition; confirm applicability using vehicle service information.

Affected system: Powertrain

Symptoms

  • Check Engine light illumination
  • Engine entering failsafe mode (limp mode)
  • Erratic or unresponsive throttle pedal input
  • Rough engine idle
  • Noticeable loss of engine power

Possible causes

  • Faulty throttle position sensor unit
  • Corroded or damaged wiring harness connectors
  • Open or short circuit in the sensor wiring
  • Internal failure of the Electronic Throttle Control (ETC) module
  • Misalignment of the tandem throttle sensors

What to check

  • Inspect the throttle body connector for corrosion or loose pins
  • Test the throttle position sensor output voltage using a multimeter
  • Check the wiring harness continuity between the sensor and the ECU
  • Verify the voltage supply and ground circuits at the sensor plug
  • Perform a throttle position relearn procedure after any repairs