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 heater circuit of a sensor that measures ammonia levels in the exhaust. It's like a thermometer that isn't warming up properly to give a good reading.
The NH3 sensor is used to measure ammonia levels in the exhaust system. The heater circuit is responsible for keeping the sensor at the correct temperature for accurate readings. A 'low' circuit condition means the heater isn't working as it should.
The P24E7 code is triggered when the Engine Control Module (ECM) detects a low voltage or resistance issue in the heater circuit of the NH3 sensor. This sensor is part of the emissions control system and helps in reducing nitrogen oxides (NOx) by monitoring ammonia levels.
• Check Engine Light is on
• Possible decrease in fuel efficiency
• Increased emissions
• Failed emissions test
• Faulty NH3 sensor
• Open or shorted wiring in the heater circuit
• Blown fuse related to the sensor heater
• Poor electrical connection at the NH3 sensor
NH3: Ammonia, a compound made of nitrogen and hydrogen.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the NH3 sensor and its wiring for damage.
• Check the fuse related to the sensor heater circuit.
• Test the voltage and resistance of the heater circuit.
• Replace the faulty NH3 sensor.
• Repair or replace damaged wiring or connectors.
• Replace a blown fuse.
• Ensure proper electrical connections at the sensor.
• OBD-II scanner
• Multimeter
• Basic hand tools (screwdrivers, pliers)
$150 - $400
Moderate
• 2015 Ford F-250
• 2016 Chevrolet Silverado
• 2017 Dodge Ram
• Regularly inspect exhaust system components.
• Ensure proper maintenance of the emissions system.
• Check for recalls related to the emissions system.
Sensor Issue
• Address this issue promptly to avoid increased emissions.
• Consult a professional mechanic if unsure.
• Do not ignore the Check Engine Light.
Check with your vehicle's manufacturer for warranty coverage on emissions-related components.
This code has become more common as emissions standards have become stricter and more vehicles are equipped with advanced emissions sensors.
Moderate – This issue should be addressed to ensure emissions compliance and optimal vehicle performance.
Driving with this code may result in failing emissions tests and increased pollution. It is advisable to repair it to comply with environmental regulations.
• Engine running
• Vehicle at operating temperature
The NH3 sensor is typically located in the exhaust system, downstream of the catalytic converter.
Q: Can I drive with a P24E7 code?
A: Driving with this code is possible, but it may lead to increased emissions and reduced fuel efficiency. It's best to fix it soon.
Q: What is an NH3 sensor?
A: An NH3 sensor measures ammonia levels in the exhaust to help control emissions.
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Fitment Required · Vehicle-fitment part
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Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
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