Powertrain
generic / SAE
P0120
Throttle Position Sensor / Switch A Circuit Malfunction
The ECU detects a general electrical fault on the throttle position sensor/switch A circuit. Signal missing, implausible, or wiring broken. Generic catch-all when no more specific TPS-A code applies.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number1 / 20
Possible causes
- TPS worn or failed (dead spot in resistive track) high
- TPS wiring or connector fault medium
- TPS mechanically misaligned to throttle shaft low
Symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
Inspection / repair
- Difficulty: medium
- DIY: possible
Pro mode: costs, time and components
Free with the newsletter by Fabian Brose: enter your name and email, confirm by mail – Pro mode is then unlocked on this device for 30 days. The newsletter arrives about every two weeks, unsubscribe at any time. Already subscribed? One click is enough – you will be recognised.
Unlock Pro mode for freeSources
References
sae:J2012