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 special pump in your car, which helps reduce pollution, is not working properly or is stuck in the 'off' position.
The P20FB code indicates an issue with the reductant pump B, which is part of the diesel exhaust fluid (DEF) system. This pump is responsible for delivering DEF to the exhaust system to reduce emissions.
The reductant pump B is part of the Selective Catalytic Reduction (SCR) system used in diesel engines to reduce nitrogen oxide emissions. When the pump is not performing as expected or is stuck in the 'off' position, the engine control module (ECM) detects this and triggers the P20FB code. This could be due to electrical issues, mechanical failure, or blockages in the system.
• Check engine light illuminated
• Reduced engine performance
• Increased emissions
• Faulty reductant pump B
• Electrical issues such as wiring or connector problems
• Blockage or restriction in the DEF line
DEF: Diesel Exhaust Fluid, a fluid used in diesel engines to reduce emissions.
SCR: Selective Catalytic Reduction, a system used to reduce nitrogen oxide emissions in diesel engines.
• Use an OBD-II scanner to confirm the P20FB code.
• Inspect the wiring and connectors for the reductant pump B.
• Check for blockages in the DEF line.
• Replace the reductant pump B if faulty.
• Repair or replace damaged wiring or connectors.
• Clear any blockages in the DEF line.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regular maintenance of the DEF system
• Use high-quality DEF fluid
• Inspect the DEF system for leaks or damage periodically
Emission Control System Issue
• Do not ignore the check engine light; get it diagnosed promptly.
• Ensure regular maintenance of the DEF system.
• Use the vehicle manual to understand DEF system maintenance.
Check with your vehicle manufacturer for warranty coverage on emission-related components.
The P20FB code has become more common with the increased use of SCR systems in diesel engines to meet emission standards.
Moderate – While the vehicle may still be drivable, it is important to address this issue to maintain emission standards and engine performance.
Driving with an active P20FB code may lead to increased emissions, which can be illegal in regions with strict emission laws.
• Engine running
• Vehicle at operating temperature
The reductant pump B is typically located near the DEF tank or along the DEF line in the vehicle's exhaust system.
Q: Can I drive with a P20FB code?
A: While you may be able to drive, it's important to fix the issue to avoid increased emissions and potential engine performance problems.
Q: What happens if I ignore the P20FB code?
A: Ignoring the code can lead to higher emissions, potential engine damage, and failing an emissions test.
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