P0447
Evaporative Emission System Vent Control Circuit Open
The ECU detected an open circuit on the EVAP vent valve control. The vent valve is needed to seal the system for leak diagnostics; with the circuit open the leak test cannot complete.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: easy
Symptoms
- Check engine light on
- Possible smell of fuel near tank or engine bay
- Failed emissions inspection
- Loose-cap warning may appear
Common causes
Ordered by how often each turns out to be the cause.
- Vent valve circuit openCommon
- Wiring or connector faultPossible
- Pin pushed back out of connector bodyLess likely
Parts involved
- EVAP Vent Valve
- Vent Valve Wiring
P0447 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.