P0123: Throttle Position Sensor/Switch A Circuit High Input
Severity: high
What it means: The throttle position sensor 'A' signal is too high.
Safe to drive? Use caution. The engine may go into reduced-power mode or respond unpredictably.
Common symptoms
- Check-engine light
- Reduced power or limp mode
- Hesitation or surging
- Erratic idle
Likely causes, ranked
- Faulty throttle position sensor or throttle bodyShop
- Wiring or connector faultDIY
- Dirty throttle bodyDIY
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What it means: The throttle position sensor 'A' signal is too high.
Severity: High. Safe to drive? Use caution. The engine may go into reduced-power mode or respond unpredictably.
DIY or shop?
Inspect the connectors and clean the throttle body. Replacing it may need a relearn.
Before you replace parts
- Read all stored codes and freeze-frame data. Fix misfire, fuel or sensor codes before chasing emissions codes.
- Check the simple things first: connectors, vacuum hoses, fluid levels and the gas cap.
- Clear the code only after a repair, then confirm it stays off after a few drives.
- Check your VIN for recalls and service bulletins.
Safety / mechanic note
Verify with a mechanic. This code can involve stalling, engine damage or loss of power. If the check-engine light is flashing, or the car stalls or runs badly, stop driving and have it inspected.
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