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 car's computer has detected a problem with the electrical circuit that controls a pump used to reduce pollution. It's like if a switch in your house wasn't working right and the light wouldn't turn on.
The P20FD code indicates that the voltage in the control circuit for the Reductant Pump B is higher than expected, which can affect the pump's operation.
The Reductant Pump B is part of the vehicle's Selective Catalytic Reduction (SCR) system, which reduces nitrogen oxide emissions. This code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the control circuit of this pump, suggesting a possible electrical issue such as a short circuit or a faulty component.
• Check Engine Light illuminated
• Possible reduction in engine performance
• Increased emissions
• Faulty reductant pump
• Wiring issues such as a short circuit
• Faulty ECM
Reductant: A substance used to reduce emissions, often diesel exhaust fluid (DEF).
SCR: Selective Catalytic Reduction, a system to reduce emissions in diesel engines.
• Use an OBD-II scanner to verify the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant pump for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the reductant pump if faulty.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Ford F-250
• Chevrolet Silverado
• RAM 2500
• Regular maintenance of the SCR system
• Ensure proper electrical connections
• Use high-quality diesel exhaust fluid (DEF)
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
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 vehicles to meet emissions standards.
Moderate – While the vehicle may still be drivable, emissions may be affected, and long-term engine damage could occur if not addressed.
Driving with a malfunctioning emissions system can lead to increased pollution and may not pass emissions testing.
• Vehicle at operating temperature
• Engine running
The reductant pump is typically located near the DEF tank, often at the rear of the vehicle.
Q: Can I drive with a P20FD code?
A: It's possible to drive, but it's not recommended as it can affect emissions and engine performance.
Q: What happens if I ignore this code?
A: Ignoring the code can lead to increased emissions and potential damage to the SCR system.
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