P0121: Throttle/Pedal Position Sensor/Switch A Circuit Range/Performance Problem

MediumPowertrainThrottle System

What does P0121 mean?

P0121 is a diagnostic trouble code indicating "Throttle/Pedal Position Sensor/Switch A Circuit Range/Performance Problem". The sensor or component is providing readings, but they fall outside the expected operating range. The part may be degraded, contaminated, or experiencing intermittent issues affecting throttle system performance.

Common causes

  • Worn or contaminated throttle system component
  • Vacuum leak or intake air leak
  • Clogged filter or restricted flow
  • Intermittent electrical connection issue

What should you do?

Schedule a diagnostic appointment at your earliest convenience. The vehicle is generally safe to drive short distances, but the underlying issue should be addressed to prevent it from worsening.

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Code P0121 can mean different things depending on your vehicle. TorqueBot gives you a diagnosis specific to your make, model, and year.

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Related codes

P0120Throttle Pedal Position Sensor/Switch A Circuit Malfunction
P0122Throttle/Pedal Position Sensor/Switch A Circuit Low Input
P0123Throttle/Pedal Position Sensor/Switch A Circuit High Input
P0124Throttle/Pedal Position Sensor/Switch A Circuit Intermittent