P0446: EVAP vent control circuit malfunction
The ECU sees an electrical fault in the valve that lets the vapour canister breathe. Typically a dirty or wet connector, or the valve itself.
| Code | P0446 |
|---|---|
| System | Engine and transmission |
| Group | P04xx, Emissions control |
| Type | Generic: it means the same on every make |
| Can you keep driving? | Yes, no rush |
What P0446 means
The vent valve opens the canister to outside air and closes it when the ECU wants to test for leaks. It usually sits by the canister near the tank, where it gets water and dirt. The ECU has found a problem in its electrical circuit.
Most common causes
- Dirty, corroded or wet valve connector
- Damaged wiring under the car
- Faulty vent valve or one jammed with dirt
- Fuse or power supply to the circuit
- ECU fault (rare)
Symptoms
- Engine warning light on
- Fuel pump nozzle keeps clicking off or the tank is hard to fill
- Other EVAP codes at the same time
- Often no symptoms
Can you drive with P0446?
Yes, no rush It does not affect driving. You can use the car normally and fix it when convenient.
Open the bonnetthe in-depth explanation
How to check it
If the nozzle keeps clicking off when you refuel, that points to a vent valve stuck closed. Look under the car by the canister to see whether the valve connector is full of mud or corrosion.
How to read and clear P0446 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P0446 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P0442 EVAP system small leak detected
- P0443 EVAP purge control valve circuit malfunction
- P0444 EVAP purge control valve circuit open
- P0445 EVAP purge control valve circuit shorted
- P0447 The evaporative emission system vent control has a broken or disconnected wire
- P0448 The evaporative emission system vent control has a short circuit
- P0449 EVAP vent valve or solenoid circuit malfunction
- P044A The exhaust gas recirculation sensor C has an electrical fault
- P0400 Exhaust gas recirculation (EGR) flow malfunction
- P0401 Exhaust gas recirculation (EGR) flow insufficient
- P0402 Exhaust gas recirculation (EGR) flow excessive
- P0403 EGR control circuit malfunction
What does code P0446 mean?
The vent valve opens the canister to outside air and closes it when the ECU wants to test for leaks. It usually sits by the canister near the tank, where it gets water and dirt. The ECU has found a problem in its electrical circuit.
Can you drive with P0446?
It does not affect driving. You can use the car normally and fix it when convenient.
How do you clear P0446?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P0446 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
