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 the computer in your car detected a problem with the pump that helps reduce pollution from the exhaust. It's like a helper pump that isn't working right.
The P20FC code indicates that the control circuit for the reductant pump B is experiencing low voltage or is not functioning properly.
The reductant pump is part of the Selective Catalytic Reduction (SCR) system in diesel engines. It pumps diesel exhaust fluid (DEF) into the exhaust stream to reduce nitrogen oxide emissions. Code P20FC is triggered when the Engine Control Module (ECM) detects a low voltage or malfunction in the control circuit of reductant pump B.
• Check Engine Light is on
• Poor engine performance
• Increased emissions
• Faulty reductant pump B
• Damaged wiring or connectors in the control circuit
• Failed ECM or software issue
Reductant: A substance used to reduce emissions, typically diesel exhaust fluid in SCR systems.
SCR: Selective Catalytic Reduction, a system used to reduce nitrogen oxide emissions in diesel engines.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant pump B for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the reductant pump B if faulty.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect and maintain the exhaust system.
• Use high-quality diesel exhaust fluid.
• Keep the vehicle's software up to date.
Sensor Issue
• Have the vehicle inspected by a professional.
• Avoid ignoring the Check Engine Light for extended periods.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has become more common with the increased use of SCR systems in diesel engines to meet emissions standards.
Moderate – It should be addressed soon to avoid potential emissions violations and performance issues.
Driving with a malfunctioning emissions system may violate emissions regulations and can lead to fines.
• Engine running
• Vehicle at operating temperature
The reductant pump is typically located near the DEF tank or along the exhaust system.
Q: Can I drive with a P20FC code?
A: It's not recommended to drive for long periods with this code, as it can lead to increased emissions and potential engine performance issues.
Q: What happens if I ignore the P20FC code?
A: Ignoring this code can result in higher emissions, potential fines, and decreased engine performance.
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