P2409
Fuel Cap Sensor or Switch Circuit Range or Performance
The sensor or switch that detects whether the fuel cap is properly closed reports a value within plausible range yet not matching driver action.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: easy
Common causes
Ordered by how often each turns out to be the cause.
- Contact drifted or dirtyCommon
Parts involved
- Fuel Cap Sensor
P2409 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.