What it means
The particulate matter sensor heater control circuit driver current or temperature is too high. The code does not identify the cause of the high reading.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The particulate matter sensor uses a heater so its sensing element can operate under exhaust conditions. P24FC means the heater driver is drawing too much current or becoming too hot, which can point to a partially shorted heater or overheating in the driver stage.
Common causes
Most likely first.
- Partial short across the heater element
- Driver overheating due to poor cooling on the module
Symptoms
- Check-engine light
- Particulate-filter or aftertreatment warning light
- Reduced engine power or performance
- Increased exhaust emissions
How to diagnose it
- Record freeze-frame data and check whether the high-current or temperature fault appears during heater activation.
- Inspect the particulate matter sensor connector and heater wiring for melted insulation, exhaust heat damage, or a short between conductors.
- With the sensor circuit isolated, test the heater element and wiring for a partial short using the manufacturer's procedure and specifications.
- Check the sensor connector for moisture, corrosion, or terminal damage that could distort current readings.
- If the heater and harness pass, assess the control module’s cooling and driver condition using the manufacturer's diagnostic steps.
Common fixes
- Repair heat-damaged or shorted heater wiring.
- Clean or replace damaged sensor connector terminals.
- Replace the particulate matter sensor if its heater element is partially shorted.
- Repair or replace the driver module if it overheats despite a sound heater circuit.
Can I keep driving?
Avoid prolonged heavy-load driving while the particulate-filter warning is active, since sensor monitoring and emissions control may be compromised. Seek prompt service if power reduction or a filter warning appears.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.