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.
Affected components
- Closed throttle switch
- Throttle position sensor
Common causes
- High likelihood: Switch out of adjustment or worn
- Medium likelihood: TPS idle voltage offset
Possible symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
Diagnostic notes
- The malfunction indicator lamp may illuminate
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.