P0446 Evaporative Emission Control System Vent Control Circuit

Description and meaning of DTC p0446

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 sothe EVAP system can pressurize and ensure there are no leaks. Evap vent valveis usually supplied 12V battery voltage with key on. The ECM's driver controls theground, and when grounded, activates the valve (closing it). If the ECM detectsa 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 unableto achieve or maintain vacuum during test.

p0446 diagnostic trouble code symptoms

There will be no obvious symptoms to driver, other than Malfunction Indicator Lamp (MIL) illumination.

DTC p0446 - possible causes

A code P0446 could mean one or more of the following has happened:Faulty vent valveOpen, short or excessive resistance on Vent valve control circuit Blockage of vent valveBad PCM

How to fix OBD-II diagnostic trouble code p0446

With a P0446 OBD-II trouble code, here are some things to try:Replace Vent valveRepair open, short, or resistance problem in control circuitRepair open, or short, or resistance problem in power circuitReplace PCMOther EVAP DTCs: P0440 - P0441 - P0442 - P0443 - P0444 - P0445 - P0447 - P0448 - P0449 - P0452 - P0453 - P0455 - P0456

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