OBD-II code guide

P0123 Throttle Position Sensor Circuit High

P0123 means the throttle position signal is higher than expected.

What it means

The computer sees a throttle signal that may not match actual throttle opening.

Common symptoms

  • Reduced engine power
  • High idle
  • Hesitation
  • Poor acceleration
  • Check engine light

Likely causes

  • Throttle position sensor issue
  • Throttle body fault
  • Wiring short
  • Connector problem
  • Accelerator pedal correlation issue

First checks

  • Do not force the throttle plate on electronic throttle bodies.
  • Check for reduced power warnings.
  • Inspect connector and wiring.
  • Scan throttle position data.