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 temperature of a special liquid used to clean up exhaust gases in your car is too cold.
The P2D45 code indicates that the temperature of the reductant, often a urea-based solution like DEF (Diesel Exhaust Fluid), is below the expected range for proper operation.
The reductant temperature sensor monitors the temperature of the Diesel Exhaust Fluid (DEF) used in the Selective Catalytic Reduction (SCR) system. If the temperature is too low, it may not function correctly, leading to improper NOx emissions control.
• Check Engine Light is on
• Reduced engine performance
• Increased emissions
• Cold ambient temperatures
• Faulty reductant temperature sensor
• Wiring issues or poor connections
DEF: Diesel Exhaust Fluid
SCR: Selective Catalytic Reduction
• Check for any other related fault codes.
• Inspect the reductant temperature sensor and its wiring.
• Test the sensor for proper operation.
• Replace the reductant temperature sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Ensure the DEF tank is properly insulated.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Use DEF with proper antifreeze properties.
• Park the vehicle in a garage during cold weather.
• Regularly check the DEF system for leaks.
Sensor Issue
• Warm up the vehicle in cold weather before driving.
• Regularly maintain the DEF system.
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 – The vehicle can still be driven, but emissions may be higher than normal.
Driving with this code may result in higher emissions, which could be illegal in some areas.
• Vehicle at operating temperature
• Ambient temperature below freezing
The reductant temperature sensor is typically located near the DEF tank or within the SCR system.
Q: What is DEF?
A: DEF stands for Diesel Exhaust Fluid, a urea-based solution used to reduce emissions in diesel engines.
Q: Can I drive with a P2D45 code?
A: Yes, but it's best to address the issue soon to ensure proper emissions control.
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