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 power going to a pump that helps reduce pollution. It's like when a toy doesn't work because its batteries are too weak.
The P05EF code indicates that the voltage supplied to the reductant pump is lower than expected, which can affect the pump's operation.
The reductant pump is part of the vehicle's Selective Catalytic Reduction (SCR) system, which reduces nitrogen oxide emissions. The pump requires a specific voltage to operate correctly. If the voltage is too low, the pump may not function properly, leading to increased emissions.
• Check Engine Light is on
• Reduced engine performance
• Increased emissions
• Faulty reductant pump
• Wiring issues such as shorts or open circuits
• Faulty power supply or relay
Reductant: A substance used in the SCR system to reduce emissions.
SCR: Selective Catalytic Reduction, a system used to reduce nitrogen oxide emissions in diesel engines.
• Use a multimeter to check the voltage at the reductant pump connector.
• Inspect the wiring and connectors for damage or corrosion.
• Test the power supply and relay for proper operation.
• Replace the reductant pump if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the power supply or relay if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Silverado
• Ford F-250
• Ram 1500
• Regularly inspect and maintain the SCR system.
• Check wiring and connectors for signs of wear.
• Ensure proper voltage supply to the pump.
Electrical Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional.
• Avoid driving the vehicle if performance is significantly reduced.
Check with your vehicle's manufacturer for warranty coverage on emissions-related components.
This code has been reported in vehicles with SCR systems since their introduction to meet emissions standards.
Moderate – Address the issue soon to avoid increased emissions and potential engine performance problems.
Driving with a malfunctioning emissions system may violate emissions regulations and result in fines.
• Engine running
• Vehicle at operating temperature
The reductant pump is usually located near the DEF (Diesel Exhaust Fluid) tank, often under the vehicle.
Q: Can I drive with a P05EF code?
A: It's not recommended to drive for extended periods with this code, as it can lead to increased emissions and potential engine performance issues.
Q: How do I reset the Check Engine Light after repairs?
A: Use an OBD-II scanner to clear the code after repairs are completed.
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