Evaporative Emission Control System Switching Valve Range/Performance Problem
Indicates a problem with the evaporative emission control system's switching valve.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The computer is detecting that the switching valve in the emissions system is not operating as it should, which can lead to increased emissions.
What the computer is actually seeing
The ECU sees a voltage or resistance reading from the HVAC valve that is outside of expected parameters, usually triggered during a self-test.
What a healthy reading looks like
Expected voltage at the switching valve connector should be around 12V when activated; resistance should be less than 5 ohms in a functional state.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect wiring and connectors at the evaporative emission control valve for damage or corrosion, repair as needed. Decision: If wiring is intact, proceed to step 2.
- 22. Check the valve operation by applying 12V directly to the valve and observe for proper opening/closing. Decision: If the valve operates correctly, proceed to step 3. If it does not, replace the valve.
- 33. Inspect for vacuum leaks in the evaporative emission control system. Use a smoke machine if available. Decision: If leaks are detected, repair them. If no leaks are present, proceed to step 4.
- 44. Use a scan tool to check for other related codes or freeze frame data that can provide insight into how and when the code triggers. Decision: If other codes are present, diagnose them; if not, suspect ECU fault.
Common causes
- Faulty switching valve
- Wiring issues between the ECU and the valve
- Vacuum leaks in the emissions system
- Faulty ECU
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but it's best to fix it soon due to potential emissions issues.
Will this code come back after clearing it?
It may come back if the underlying issue is not fixed.
Why does this code appear with other emissions codes?
Emissions systems are interconnected, so a problem in one area can affect others.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
Start guided diagnostic →