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 checks the temperature of a special fluid used to clean the car's exhaust is not working right. It's like a thermometer that's not showing the right temperature.
The P2ACE code is triggered when the Engine Control Module (ECM) detects a low voltage signal from the Reductant Temperature Sensor B, indicating a possible issue with the sensor circuit.
The reductant temperature sensor is part of the vehicle's Selective Catalytic Reduction (SCR) system, which reduces emissions. The sensor monitors the temperature of the diesel exhaust fluid (DEF) to ensure it is within the optimal range for effective operation. A 'circuit low' condition suggests that the sensor is sending a voltage signal lower than expected, possibly due to a wiring issue, a faulty sensor, or a problem with the ECM.
• Check Engine Light illuminated
• Reduced engine performance
• Increased emissions
• Faulty reductant temperature sensor
• Damaged or corroded wiring or connectors
• Faulty Engine Control Module (ECM)
Reductant: A substance used to reduce emissions, such as diesel exhaust fluid.
SCR: Selective Catalytic Reduction, a system that reduces nitrogen oxide emissions in diesel engines.
• 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.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly inspect and maintain the SCR system.
• Ensure proper DEF levels and quality.
• Check wiring and connections for wear and tear.
Sensor Issue
• Don't ignore the Check Engine Light.
• Have the vehicle inspected by a professional.
• Avoid driving long distances until the issue is resolved.
Check with your vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has been associated with vehicles using SCR systems to meet emissions standards, particularly in diesel engines.
Moderate – Addressing this issue is important to maintain vehicle performance and emissions compliance.
Driving with a malfunctioning emissions system may violate emissions regulations and can lead to fines.
• Engine must be running.
• Vehicle should be at operating temperature.
The reductant temperature sensor is typically located near the DEF tank or within the SCR system.
Q: Can I drive my car with a P2ACE code?
A: It's not recommended to drive for long periods with this code active, as it can affect emissions and performance.
Q: How do I reset the Check Engine Light after fixing the issue?
A: Use an OBD-II scanner to clear the code after repairs are complete.
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