Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of your car that helps keep a special fluid warm. This fluid helps clean the car's exhaust so it's not as dirty.
The P24D2 code indicates an issue with the sensor circuit for the reductant heater A. This heater is part of the system that warms the diesel exhaust fluid (DEF) to ensure it works properly in reducing emissions.
The reductant heater is responsible for maintaining the diesel exhaust fluid at an optimal temperature for effective emission reduction. The sensor circuit monitors the heater's operation. If the circuit detects an abnormal condition, such as an open or short, it triggers the P24D2 code.
• Check engine light is on
• Poor vehicle performance
• Increased emissions
• Faulty reductant heater
• Damaged wiring or connectors in the heater circuit
• Faulty sensor in the heater circuit
Reductant: A substance used to reduce emissions, often referring to diesel exhaust fluid.
DEF: Diesel Exhaust Fluid, a solution used to reduce harmful emissions from diesel engines.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the reductant heater and sensor for proper operation.
• Replace the faulty reductant heater.
• Repair or replace damaged wiring or connectors.
• Replace the faulty sensor.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly inspect the exhaust system components.
• Ensure proper maintenance of the DEF system.
• Check for recalls related to the reductant heater.
Sensor Issue
• Do not ignore the check engine light.
• Have the vehicle inspected by a professional if unsure.
• Regularly maintain the DEF system.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
The P24D2 code has become more common with the increased use of DEF systems in diesel engines to meet emission standards.
Moderate – While the vehicle may still operate, emissions may increase, and performance can be affected.
Driving with increased emissions may violate local environmental regulations.
• Engine running
• DEF system active
The reductant heater is typically located within the DEF tank or along the DEF delivery lines.
Q: Can I drive with a P24D2 code?
A: It's possible, but not recommended due to increased emissions and potential performance issues.
Q: How often should I check the DEF system?
A: Regularly as part of your vehicle's maintenance schedule, or more frequently if you experience issues.
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