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 is having trouble getting a steady reading from a sensor that checks the temperature of a special liquid used to clean up exhaust gases.
The P2AD0 code is triggered when the engine control module (ECM) detects an intermittent signal from the reductant temperature sensor B. This sensor monitors the temperature of the diesel exhaust fluid (DEF).
The reductant temperature sensor B is part of the selective catalytic reduction (SCR) system, which reduces nitrogen oxide emissions in diesel engines. An intermittent circuit issue means the sensor is not providing a consistent signal, which could affect the DEF system's performance.
• Check Engine Light illuminated
• Poor fuel economy
• Possible increase in emissions
• Faulty reductant temperature sensor B
• Wiring or connector issues in the sensor circuit
• Corroded or damaged connectors
Reductant: A substance used to reduce emissions, often diesel exhaust fluid (DEF).
SCR: Selective Catalytic Reduction, a system to reduce 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 sensor's resistance and output signal.
• Replace the reductant temperature sensor B if faulty.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect the DEF system components.
• Ensure connectors are clean and free of corrosion.
• Follow the manufacturer's maintenance schedule.
Sensor Issue
• Address the issue promptly to avoid increased emissions.
• Consider professional diagnosis if unsure about repairs.
Check vehicle warranty for coverage on emissions-related components.
This code has become more common with the increased use of SCR systems in diesel engines to meet emissions standards.
Moderate – While the vehicle may still be drivable, emissions and fuel efficiency may be affected.
Driving with a malfunctioning emissions system may violate emissions regulations.
• Engine at operating temperature
• Vehicle driven under normal conditions
The reductant temperature sensor B is typically located near the DEF tank or along the DEF line.
Q: Can I drive with the P2AD0 code?
A: Yes, but it's best to fix it soon to avoid emissions issues.
Q: What happens if I ignore this code?
A: Ignoring it can lead to increased emissions and potential damage to the SCR system.
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