P2420EVAP System Switching Valve Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2420 means the control circuit of the EVAP switching valve reads high - typically a short to battery voltage on the control line or an overcurrent detected by the driver stage. Karma lists P2420 for the rear fuel tank isolation valve of the Revero and GS-6, which the ECM operates, and Subaru's bulletin 09-103-23 for 2015 Legacy/Outback with an evaporative leak check module (ELCM) includes P2420 among the codes to check alongside the pump fault P2404. Ford instead reports all circuit faults of its switching valve as P2418. CARB requires output components to be monitored for circuit faults. P2419 is the low-side fault and P2418 the open circuit. The evap leak monitor cannot run until the circuit is repaired.
- What you may notice
- Check engine light
- EVAP readiness not set
- No noticeable driveability change
- Likely causes
- LikelyControl wire shorted to battery voltage
- PossibleSwitching valve coil with too low resistance (overcurrent)
- RareFaulty driver stage in the ECM
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.