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 computer in the car is having trouble getting a steady reading from a sensor that checks the temperature of a special fluid used to clean the exhaust. It's like trying to read a thermometer that keeps changing its numbers quickly.
The P2046 code is triggered when the engine control module (ECM) detects an intermittent signal from the reductant temperature sensor A circuit.
The reductant temperature sensor is part of the diesel exhaust fluid (DEF) system, which helps reduce harmful emissions. This sensor monitors the temperature of the DEF to ensure it is at the correct temperature for optimal performance. An intermittent circuit means the signal from the sensor is not stable, which can affect the system's efficiency.
• Check Engine Light is on
• Poor fuel efficiency
• Increased emissions
• Faulty reductant temperature sensor
• Damaged or corroded wiring/connectors
• Issues with the ECM
DEF: Diesel Exhaust Fluid, a fluid used to reduce emissions in diesel engines.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant temperature sensor for proper operation.
• Replace the reductant temperature sensor if faulty.
• Repair or replace damaged wiring/connectors.
• Reprogram or replace the ECM if needed.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly inspect and maintain the DEF system.
• Ensure connectors are clean and secure.
• Use high-quality DEF fluid.
Sensor Issue
• If you notice the Check Engine Light, have your vehicle checked as soon as possible.
• Maintain regular service intervals for your vehicle's emission system.
Check with your vehicle manufacturer for warranty coverage on emission-related components.
This code has become more common with the increased use of DEF systems in diesel vehicles to meet stricter emission standards.
Moderate – While the vehicle may still operate, it's important to address this issue to maintain emission compliance and efficiency.
Ignoring emission-related issues can lead to failing emission tests and may be illegal in some regions.
• Engine at operating temperature
• Stable driving conditions
The reductant temperature sensor is typically located near the DEF tank or in the DEF line.
Q: Can I drive with a P2046 code?
A: While you can drive with this code, it's best to fix it soon to avoid increased emissions and potential damage to the DEF system.
Q: How often should I check the DEF system?
A: Regularly inspect during routine maintenance or if the Check Engine Light comes on.
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