What does the code P0446?
P0446: Evaporative Emission Control System Vent Control Circuit. Trouble code P0446 typically turns up in On-Board Diagnostic testing on account of an illuminated Check Engine Malfunction Indicator Lamp. This generic OBD-II code indicates that the evaporative vent valve in the emission control system is malfunctioning.
What does the code p0446 mean on a car?
The code P0446 is triggered by the engine computer (ECU) when there’s a malfunction in the EVAP control system vent control valve. How does the EVAP system vent control work? The Evaporative (EVAP) Emission Control System is one of the methods your engine uses to limit its harmful emissions.
What does p0446 do to the EVAP system?
During the leak test, the ECM closes the vent control valve to create a sealed EVAP system. When P0446 is triggered, the ECM has detected a short in the circuitry to activate the vent control valve, or the EVAP system failed to maintain the proper pressure during the active EVAP leak test. What Are The Symptoms Of P0446?
When to repair a check engine light p0446?
The driver will likely not notice any symptoms associated with P0446 other than the check engine light being on. However, as with all check engine light diagnostic trouble codes, you should repair it as soon as possible to return the vehicle to normal operation. Scan your vehicle to verify P0446 is the only code present.
When does the p0441 code trigger in the ECM?
If the valve fails to close or a vacuum cannot be maintained during this test, the P0441 code will trigger in the ECM. To fix this problem in your Toyota, you’ll need to test the vent valve circuit from the ECM to the valve to ensure that it’s closing and receiving power when the key is on (the engine does not have to be running).
What causes OBDII code p0440?
- or loose.
- The fuel tank is leaking or damaged.
- or any component of the fuel vapor system.
- The fuel vapor pressure sensor is faulty.
- or damaged.
- The vent valve is defective.
What are the probable causes of DTC p0440?
- Missing or loose fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- EVAP canister or fuel tank leaks
- EVAP system hose leaking
- Fuel tank leaking
What is diagnostic code p0440?
P0440 is a diagnostic trouble code (DTC) for “Evaporative Emission Control System Malfunction”. This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation.
What are codes p0440 and p1665?
Many EVAP system faults can cause a P0440 to set. A faulty EVAP Vent Solenoid may cause a P0440 to set. A P1665 is an Evap Vent Solenoid specific code. It indicates an improper voltage level has been detected on the output circuit which controls the EVAP Canister Vent Solenoid Valve. The vent solenoid or its circuit is what you should focus on first.