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 thinks the sensor that checks the temperature of the stuff coming out of the exhaust is getting too high of a signal. It's like when a thermometer is saying it's way hotter than it really is.
The P24C9 code is triggered when the vehicle's engine control module (ECM) detects a high voltage signal from the particulate matter sensor temperature circuit, indicating a potential issue with the sensor or its circuit.
The particulate matter sensor is part of the vehicle's emissions control system, used to monitor the amount of soot or particulate matter in the exhaust gases. The sensor also measures temperature to ensure accurate readings. A 'high' circuit condition means the sensor is outputting a voltage higher than expected, which could be due to a malfunctioning sensor, wiring issues, or other electrical problems.
• Check Engine Light illuminated
• Possible decrease in fuel efficiency
• Potential increase in exhaust emissions
• Faulty particulate matter sensor
• Wiring issues such as shorts or open circuits
• Faulty ECM or PCM
ECM: Engine Control Module
PCM: Powertrain Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the particulate matter sensor and its wiring for damage.
• Test the sensor's voltage output with a multimeter.
• Replace the particulate matter 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 - $400
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regular maintenance and inspection of the exhaust system.
• Ensure proper fuel quality to reduce soot production.
• Address any exhaust leaks promptly.
Sensor Issue
• Do not ignore the Check Engine Light; get it diagnosed promptly.
• Consider routine checks of the exhaust system to prevent future issues.
Check with the vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has become more common with the introduction of stricter emissions standards and the use of particulate matter sensors in diesel engines.
Moderate – While the vehicle may still be drivable, emissions and fuel efficiency could be affected.
Ignoring emissions-related issues can lead to increased pollution and may violate local emissions laws.
• Engine at operating temperature
• Vehicle in a safe location to perform tests
The particulate matter sensor is typically located in the exhaust system, near the diesel particulate filter.
Q: Can I drive with a P24C9 code?
A: While you may be able to drive, it's not recommended as it can affect emissions and fuel efficiency.
Q: How can I prevent this code from appearing?
A: Regular maintenance and using quality fuel can help prevent issues with the particulate matter sensor.
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