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ENRUDEPLES

P0123 — Throttle/Pedal Position Sensor/Switch "A" Circuit High Input

moderate

What it means

The signal voltage from throttle position sensor A has risen above the calibrated limit, usually more than about 4.8 V, and stays high even with the pedal released. The ECM reads a wide open throttle that does not exist, which corrupts load calculation and fuel metering. Symptoms include a lit MIL, high or surging idle, sudden loss of power when the ECM forces limp-home mode, and rich running with rough engine operation.

Likely causes (most common first)

  1. Signal wire shorted to the 5 V reference or to battery voltage
  2. Open or high resistance in the sensor ground circuit
  3. Internally failed throttle or pedal position sensor
  4. Throttle plate mechanically stuck open or binding linkage
  5. Damaged connector with pushed-back or bent terminals
  6. Faulty engine control module

Can you drive with it?

Driving is unsafe because idle can run high and power may drop without warning, so repair before further use.

This is the generic meaning. What about your car?

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