P0446 Mercedes-Benz Code - Evaporative Emission Control System Vent Control Circuit Malfunction
Quick Answer
The Evaporative System (EVAP) canister vent control valve is located on the EVAP canister and is used to seal the canister vent. Common causes include Missing Fuel cap, Incorrect fuel filler cap used, Fuel filler cap remains open or fails to close. Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
- What it means
- P0446 Mercedes-Benz indicates Evaporative Emission Control System Vent Control Circuit Malfunction.
- Common causes
- Common causes include Missing Fuel cap, Incorrect fuel filler cap used, Fuel filler cap remains open or fails to close.
- Severity
- Low - monitor the vehicle and repair when practical.
- Can I drive?
- The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
Code P0446 Mercedes-Benz Description
This solenoid valve responds to signals from the Engine Control Module (ECM). When the ECM sends an ON signal, the coil in the solenoid valve is energized. A plunger will then move to seal the canister vent. The ability to seal the vent is necessary for the on board diagnosis of other evaporative emission control system components.
This solenoid valve is used only for diagnosis, and usually remains opened.
What are the Possible Causes of the DTC P0446 Mercedes-Benz?
- Missing Fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- Vent control valve harness is open or shorted
- Vent control valve circuit poor electrical connection
- Faulty vent control valve
How to Fix the DTC P0446 Mercedes-Benz?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0446 Mercedes-Benz code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P0446 Mercedes-Benz Code
1. What is OBDII code P0446 in a Mercedes-Benz?
- OBDII code P0446 in a Mercedes-Benz indicates a malfunction in the Evaporative Emission Control System Vent Control Circuit.
2. What are the common symptoms of a P0446 code in a Mercedes-Benz?
- Common symptoms of a P0446 code include the check engine light coming on, decreased fuel efficiency, and a strong fuel odor.
3. What are the possible causes of a P0446 code in a Mercedes-Benz?
- Possible causes of a P0446 code include a faulty vent control valve, a damaged charcoal canister, loose or damaged fuel cap, or issues with the wiring or connectors in the vent control circuit.
4. How can I diagnose a P0446 code in my Mercedes-Benz?
- Diagnosing a P0446 code involves checking the vent control valve, testing the charcoal canister, inspecting the fuel cap, and examining the wiring and connectors for any damage or corrosion.
5. Can I continue driving my Mercedes-Benz with a P0446 code?
- While it may be possible to drive with a P0446 code, it is recommended to address the issue promptly to prevent potential damage to the vehicle's emission control system.
6. How can I repair a P0446 code in my Mercedes-Benz?
- Repairing a P0446 code often involves replacing the vent control valve, repairing or replacing the charcoal canister, ensuring the fuel cap is tightened properly, and repairing any wiring or connector issues.
7. Are there any DIY tips for fixing a P0446 code in a Mercedes-Benz?
- DIY tips for addressing a P0446 code include checking and tightening the fuel cap, visually inspecting the wiring and connectors for any obvious issues, and ensuring the vent control valve is functioning correctly.
8. Will resetting the OBDII code clear a P0446 code in a Mercedes-Benz?
- Resetting the OBDII code may temporarily clear the P0446 code, but if the underlying issue is not addressed, the code is likely to reappear.
9. How important is it to fix a P0446 code in a Mercedes-Benz?
- It is important to fix a P0446 code in a Mercedes-Benz to ensure the vehicle's emission control system is functioning properly, maintain fuel efficiency, and prevent potential damage to other components.
10. Can a P0446 code in a Mercedes-Benz cause other problems if left unresolved?
- If left unresolved, a P0446 code in a Mercedes-Benz can potentially lead to decreased fuel efficiency, increased emissions, and may trigger additional codes related to the vehicle's emission control system.
Discuss the causes and fixes for P0446 Mercedes-Benz OBDII Code
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The "Fuel Tank Pressure Sensor" is located at the top in the Fuel Level Sensor, and the Fuel Level Sensor is on top of the Fuel Tank.
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