P0446 Evaporative Emission Control System Vent Control Circuit Malfunction
OBD-II Trouble Code Technical Description
Evaporative Emission Control System Vent Control Circuit Malfunction
What does that mean?
This diagnostic trouble code (DTC) is a generic OBD-II powertrain code. It is considered generic because it applies to all makes and models of vehicles (1996-newer), although specific repair steps may vary depending on the model.
Evap vent valve has only one purpose. It closes in order to seal the vent so the EVAP system can pressurize and ensure there are no leaks. Evap vent valve is usually supplied 12V battery voltage with key on.
The ECM’s driver controls the ground, and when grounded, activates the valve (closing it). If the ECM detects a short to ground, and open,or a short to battery voltage on the control circuit, P0446 will set. Code also may refer to ECM detecting that EVAP system is unable to achieve or maintain vacuum during test.
Symptoms
There will be no obvious symptoms to driver, other than Malfunction Indicator Lamp (MIL) illumination.
Causes
A code P0446 could mean one or more of the following has happened:
Possible Solutions
With a P0446 OBD-II trouble code, here are some things to try:
Other EVAP DTCs: P0440 – P0441 – P0442 – P0443 – P0444 – P0445 – P0447 – P0448 – P0449 – P0452 – P0453 – P0455 – P0456
Need help?
Let us fix your problem. You are most welcome our diagnosis experts have in most cases the knowledge and skills to find the cause of the error code p0446 and to solve the problems.
Make an appointment for diagnosis
"Delete Error Code Permanently, Disable DTC Error Code Function for p0446 in the ECU"
In extreme cases, we even have the option to permanently remove the specific DTC p0446 and disable the function of the specific error code in the ECU. All other fault code functions will then continue to work to protect the engine. This is different from clearing an error code with a diagnostic device. We have the option to permanently remove the function of the specific error code, so that it never comes back. Also emergency running that occurs on the specific error code can be solved in most cases.
Of course we prefer to first try to solve the cause of the error code, but sometimes the only solution is to permanently disable the DTC function of p0446.
