EVAP Leak Detection Pump Sense Circuit Range/Performance
The sense (reed-switch or current-feedback) signal from the leak-detection pump is electrically valid but does not match expectations during a leak test. Often a worn pump diaphragm or a sticking reed contact.
Affected components
- Evap leak detection pump
- Evap pump wiring
Common causes
- High likelihood: Pump diaphragm worn
- Medium likelihood: Reed switch intermittent
- Low likelihood: Sensor element aged beyond calibration window
Possible symptoms
- Check engine light on
- Possible smell of fuel near tank or engine bay
- Failed emissions inspection
- Loose-cap warning may appear
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Related codes
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.