EVAP Switching Valve Control Circuit Performance
The evaporative switching valve — used on multi-path EVAP systems to route purge or pressure-test flow — does not respond as expected. Self-test fails because tank pressure does not change in the calibrated direction.
Affected components
- Evap switching valve
- Evap lines
Common causes
- High likelihood: Switching valve failed
- Medium likelihood: EVAP line blocked or kinked
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
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.