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 a sensor in your car that checks the temperature of a special fluid used to clean the exhaust isn't working right.
The P2ACC code is triggered when the Engine Control Module (ECM) detects a fault in the circuit of the reductant temperature sensor B, which is responsible for monitoring the temperature of the diesel exhaust fluid (DEF).
The reductant temperature sensor B is part of the vehicle's selective catalytic reduction (SCR) system, which reduces harmful emissions. This sensor monitors the temperature of the DEF to ensure it is within the optimal range for effective operation. A fault in this sensor's circuit can lead to improper SCR function and increased emissions.
• Check Engine Light is on
• Increased vehicle emissions
• Possible reduction in engine performance
• Faulty reductant temperature sensor B
• Damaged or corroded wiring or connectors
• Faulty ECM
ECM: Engine Control Module
SCR: Selective Catalytic Reduction
DEF: Diesel Exhaust Fluid
• Use an OBD-II scanner to confirm the P2ACC code.
• Visually inspect the wiring and connectors for damage or corrosion.
• Test the reductant temperature sensor B for proper operation.
• Replace the reductant temperature sensor B if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect and maintain the SCR system.
• Use high-quality diesel exhaust fluid.
• Ensure all connectors and wiring are secure and free from corrosion.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regularly maintain the vehicle's emission control systems.
Check with your vehicle manufacturer for warranty coverage on emission-related components.
This code has become more common with the increased use of SCR systems in diesel vehicles to meet stricter emission standards.
Moderate – Address the issue soon to avoid potential emission test failures and ensure optimal vehicle performance.
Ignoring emission-related issues may lead to failing emissions tests and can be illegal in some regions.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The reductant temperature sensor B is typically located near the DEF tank or within the SCR system.
Q: Can I drive with a P2ACC code?
A: While the vehicle may still be drivable, it's best to address the issue to avoid increased emissions and potential damage to the SCR system.
Q: How do I reset the P2ACC code?
A: After fixing the issue, you can use an OBD-II scanner to clear the code. If the problem persists, the code may reappear.
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