Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that a part of the car that helps clean the exhaust is not working properly because a valve is stuck and won't open.
The P20DC code indicates an issue with the fuel supply control for the exhaust aftertreatment system, where the control is stuck in the closed position.
The Exhaust Aftertreatment Fuel Supply Control is responsible for regulating the amount of fuel delivered to the aftertreatment system, which helps reduce emissions. When this control is stuck closed, it means that no additional fuel is being supplied, which can lead to ineffective emission control.
• Check Engine Light is on
• Increased emissions
• Reduced engine performance
• Faulty fuel supply control valve
• Wiring issues in the control circuit
• Malfunctioning control module
Aftertreatment: A process to reduce emissions from the exhaust system.
Fuel Supply Control: A system that regulates the amount of fuel delivered to the engine or aftertreatment system.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the fuel supply control valve for proper operation.
• Replace the faulty fuel supply control valve.
• Repair or replace damaged wiring or connectors.
• Update or replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $500
Moderate
• Chevrolet Silverado
• Ford F-250
• Ram 2500
• Regular maintenance of the exhaust system
• Timely replacement of faulty components
• Ensure proper fuel quality
Emission Control Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid driving the vehicle for extended periods until repaired.
Check if the vehicle's emission system is covered under warranty.
This code has been associated with vehicles that have advanced emission control systems, particularly diesel engines.
Moderate – It should be addressed soon to avoid increased emissions and potential engine performance issues.
Driving with increased emissions may violate local environmental regulations.
• Engine running at operating temperature
• Vehicle stationary with no load
The exhaust aftertreatment fuel supply control valve is typically located near the exhaust system, often under the vehicle.
Q: Can I drive with a P20DC code?
A: It's not recommended to drive for long periods with this code as it can lead to increased emissions and potential engine issues.
Q: How can I reset the P20DC code?
A: You can reset the code using an OBD-II scanner, but it's important to fix the underlying issue first.
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