P0510
Closed Throttle Position Switch
The dedicated closed-throttle switch (or closed-throttle bit on the TPS) does not behave as expected - either it never activates, never deactivates, or shows incoherent state against TPS voltage and engine load. Used by older systems for fuel-cutoff and idle recognition.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: easy
Symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
Common causes
Ordered by how often each turns out to be the cause.
- Switch out of adjustment or wornCommon
- TPS idle voltage offsetPossible
Parts involved
- Closed Throttle Switch
- Throttle Position Sensor
P0510 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.