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 sensor that checks the temperature of a special tank in your car is not working right all the time. It's like a thermometer that sometimes gives the wrong reading.
The P2ADD code indicates that the signal from the reductant tank temperature sensor B is not stable. It may be sending inconsistent or erratic data to the engine control module (ECM).
The reductant tank temperature sensor B monitors the temperature of the reductant (DEF) tank. An intermittent or erratic signal from this sensor may cause the ECM to misinterpret the temperature, potentially affecting the emissions control system.
• Check Engine Light illuminated
• Possible reduction in fuel efficiency
• Potential increase in emissions
• Faulty reductant tank temperature sensor B
• Wiring issues such as loose connections or damaged wires
• Faulty ECM or software issues
Reductant: A fluid used in diesel engines to reduce emissions.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the P2ADD code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant tank temperature sensor B for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the reductant tank temperature sensor B if faulty.
• Update or reprogram the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect wiring and connectors for damage.
• Ensure proper maintenance of the reductant system.
• Keep software and ECM updates current.
Sensor Issue
• Address the issue promptly to avoid potential emissions problems.
• Consult a professional mechanic if unsure about the repair.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has been reported in vehicles with diesel engines that use a reductant system for emissions control.
Moderate – It should be addressed soon to maintain emissions control and vehicle efficiency.
Ignoring emissions-related codes may result in failing emissions tests and potential fines.
• Engine at normal operating temperature
• Vehicle stationary and engine idling
The reductant tank temperature sensor is located near or on the DEF tank, typically under the vehicle.
Q: Can I drive with a P2ADD code?
A: You can drive, but it's best to fix the issue soon to avoid emissions problems.
Q: How do I clear a P2ADD code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is resolved first.
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