EVAP Control System Fault
Indicates a fault in the EVAP control circuit.
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 EVAP system captures fuel vapors to prevent them from escaping into the atmosphere; a circuit fault means the computer can't monitor this properly.
What the computer is actually seeing
The Engine Control Module (ECM) expects signals from the EVAP control solenoid and pressure sensors but detects an open or shorted circuit, causing a fault code to set.
What a healthy reading looks like
Valve should show about 5-12 volts at the control circuit with the key on and engine off. Resistance of solenoid should be around 20-30 ohms.
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 the wiring and connectors for the EVAP control solenoid. Look for frays, corrosion, or damage.
- 22. Check the voltage at the EVAP control solenoid with the key on (engine off). Should be 5-12 volts. No voltage? Go to step 3. Voltage present? Go to step 4.
- 33. If there's no voltage, trace the wiring back to the ECU. Look for shorts or opens. Repair as necessary and retest.
- 44. If voltage is present, measure the resistance of the solenoid. Should be 20-30 ohms. If it's out of this range, replace the solenoid. If it's in range, consider the ECM as a possible fault.
Common causes
- Damaged wiring or connectors in the EVAP system
- Faulty EVAP control solenoid
- Bad ground connection for the EVAP components
- ECM malfunction
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's moderate severity; you can drive but should address it soon to avoid emissions issues.
Will this code come back after clearing?
If the issue isn't fixed, yes, the code will return.
Why does this code sometimes pair with P0440?
Both codes relate to the EVAP system, indicating a common problem area.
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