When does the ECM lock out the EVAP function?
If the ECM attempts to activate the vent control solenoid but detects incorrect voltage feedback or incorrect vacuum or pressure feedback, it will lock out EVAP function, set a diagnostic trouble code (DTC), and illuminate the malfunction indicator lamp (MIL). DTC P0446 is defined as “Evaporative Emission (EVAP) Vent Control Circuit Malfunction.”
What does an EVAP canister vent control valve do?
What Does an EVAP Canister Vent Control Valve Do? The Evaporative Emission Control System (EVAP) keeps fuel vapors from leaking into the atmosphere by collecting and storing the vapors in a canister filled with carbon pellets.
What is the code for the EVAP vent?
The evap vent valve in most makes and models depends on a supply of a 12V battery voltage with key on. The ECM driver closes this valve when grounded and will set code P0446 if there is an open or short to ground or battery voltage or it is not possible to form a vacuum seal.
What happens when the EVAP valve is stuck?
In most cases, you will not notice any symptoms other than the MIL and slightly reduced engine performance and fuel economy, depending on whether the ECM goes into “limp-home” mode or not. If the EVAP vent control valve is stuck open, you may notice a fuel odor. This DTC may be accompanied by other EVAP system DTCs.
How does the ECM work on an EVAP vent?
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.
What happens when a Nissan vent valve fails?
There were other issues but the vent valve constantly emerged on the list. Nissan manufacturers install Evaporative Emission Control (EVAP) systems in their vehicles to address the fuel escaping process properly. When the EVAP leaks or fails, fuel vapors get into the atmosphere.
The evap vent valve in most makes and models depends on a supply of a 12V battery voltage with key on. The ECM driver closes this valve when grounded and will set code P0446 if there is an open or short to ground or battery voltage or it is not possible to form a vacuum seal.
How does the p0446 EVAP vent valve work?
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.