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 thinks the sensor that measures the temperature of a special fluid used to clean the car's exhaust is reading too high. It's like a thermometer showing a temperature that's too hot.
The P2045 code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the reductant temperature sensor circuit, which monitors the temperature of the Diesel Exhaust Fluid (DEF).
The reductant temperature sensor is part of the Selective Catalytic Reduction (SCR) system, which reduces emissions in diesel engines. A 'circuit high' condition indicates that the sensor is sending a voltage signal that is higher than the expected range, which could be due to a faulty sensor, wiring issues, or a problem with the ECM.
• Check Engine Light illuminated
• Possible reduction in fuel efficiency
• Potential increase in emissions
• Faulty reductant temperature sensor
• Wiring issues such as open or short circuits
• Faulty Engine Control Module (ECM)
Reductant: A substance used to reduce emissions, often Diesel Exhaust Fluid (DEF) in diesel engines.
SCR: Selective Catalytic Reduction, a system used 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 temperature sensor with a multimeter.
• Replace the reductant temperature sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly inspect and maintain the SCR system.
• Ensure proper DEF quality and levels.
• Check wiring and connectors for wear.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional.
• Regular maintenance can prevent this issue.
Check with the vehicle manufacturer for specific warranty coverage on emissions-related components.
This code is commonly associated with diesel vehicles equipped with SCR systems to meet emissions standards.
Moderate – While the vehicle may still be operable, emissions and fuel efficiency may be affected.
Driving with a malfunctioning emissions system may violate emissions regulations and contribute to environmental pollution.
• Engine at operating temperature
• Vehicle stationary
The reductant temperature sensor is typically located near the DEF tank or within the SCR system.
Q: Can I drive with a P2045 code?
A: It's possible to drive, but it's not recommended as it may affect emissions and fuel efficiency.
Q: How do I reset the Check Engine Light after fixing the issue?
A: Use an OBD-II scanner to clear the code after the repair is completed.
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