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 has detected a problem with the power supply to a sensor that checks for ammonia (NH3) in the exhaust. It's like when a toy doesn't work because its batteries are dead or not connected properly.
The P24EA code is triggered when the Engine Control Module (ECM) detects an issue with the voltage supply to the NH3 sensor, which is responsible for monitoring ammonia levels in the vehicle's exhaust system.
The NH3 sensor is part of the vehicle's emissions control system. It monitors ammonia levels in the exhaust to ensure the Selective Catalytic Reduction (SCR) system is functioning correctly. The P24EA code indicates that the ECM has detected a problem with the voltage supply to this sensor, which can affect its ability to accurately measure ammonia levels.
• Check Engine Light illuminated
• Possible reduction in fuel efficiency
• Increased emissions
• Faulty NH3 sensor
• Damaged wiring or connectors
• Faulty ECM
NH3: Ammonia, a compound of nitrogen and hydrogen.
ECM: Engine Control Module, the computer that controls the engine's functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the NH3 sensor and its wiring for damage.
• Check the voltage supply to the NH3 sensor.
• Replace the NH3 sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $600
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect and maintain the exhaust system.
• Ensure proper electrical connections to sensors.
• Use high-quality fuel to reduce emissions.
Sensor Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid ignoring the Check Engine Light for extended periods.
• Consider regular maintenance to prevent sensor issues.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has become more common with the increased use of SCR systems in diesel vehicles to meet emissions standards.
Moderate – While the vehicle may still be drivable, it's important to address emissions issues promptly to avoid further damage.
Driving with malfunctioning emissions systems may violate environmental regulations and can lead to fines.
• Engine at operating temperature
• Vehicle in closed-loop mode
The NH3 sensor is typically located in the exhaust system, downstream of the SCR catalyst.
Q: What does the NH3 sensor do?
A: The NH3 sensor measures ammonia levels in the exhaust to ensure the emissions system is working properly.
Q: Can I drive with a P24EA code?
A: While you may be able to drive, it's best to address the issue promptly to avoid increased emissions and potential damage.
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Fitment Required · Vehicle-fitment part
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.