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 that checks the temperature of a special fluid in your car is reading too high. It's like a thermometer that's saying it's too hot.
The P2ACF code indicates that the reductant temperature sensor B is reporting a voltage signal that is higher than the expected range. This suggests an issue with the sensor or its circuit.
The reductant temperature sensor B monitors the temperature of the diesel exhaust fluid (DEF) used in the selective catalytic reduction (SCR) system. A high circuit signal could mean a short circuit, an open circuit, or a faulty sensor.
• Check Engine Light is on
• Possible reduction in fuel efficiency
• Potential issues with emissions control
• Faulty reductant temperature sensor B
• Wiring issues such as a short or open circuit
• Poor electrical connections
Reductant: A substance used to reduce emissions in diesel engines, often diesel exhaust fluid (DEF).
SCR: Selective Catalytic Reduction, a system used to reduce emissions in diesel engines.
• Use an OBD-II scanner to confirm the P2ACF code.
• 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.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• RAM 2500
• Regularly inspect wiring and connectors for damage.
• Ensure proper maintenance of the SCR system.
• Use high-quality diesel exhaust fluid.
Sensor Issue
• Address the issue promptly to avoid emissions problems.
• Consult a professional if unsure about the repair.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has become more common with the increased use of SCR systems in diesel engines.
Moderate – It should be addressed soon to ensure proper emissions control.
Ignoring this code could lead to increased emissions, which may not comply with environmental regulations.
• Engine at operating temperature
• Vehicle in a safe, stationary position
Typically located near the DEF tank or along the DEF line.
Q: Can I drive with the P2ACF code?
A: It's possible to drive, but it's best to fix the issue soon to avoid emissions problems.
Q: What happens if I ignore this code?
A: Ignoring it can lead to reduced fuel efficiency and increased emissions, potentially causing further damage.
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A wired color-screen reader with readiness hotkeys, live data, code definitions, and data logging.
Good for emissions-related codes because it exposes readiness monitors and live powertrain data.
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Specialty · Smoke machine
Helpful for finding EVAP and vacuum leaks that are hard to see with visual inspection alone.
Helpful for tracking down EVAP and vacuum leaks that can trigger emissions faults.
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Helpful when the code points toward exhaust or oxygen-sensor work and space is tight.
Useful when the diagnosis points toward oxygen-sensor removal or replacement.
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