P24FC code meaning
Particulate Matter Sensor Heater Control Circuit Driver Current/Temperature Too High
Powertrain system Generic code P24xx codes Check engine light
What P24FC means
P24FC concerns the output stage that powers the heater of the particulate matter sensor: the driver reports excessive current or an internal temperature past its limit, which suggests a heater with shorted turns or too little resistance, or an overheating sensor electronics unit. On heavy trucks this sensor works as a self-diagnosing device after the SCR catalyst and reports over J1939. Volvo and Mack list P24FC00 in two editions of their PM sensor diagnosis guide for US14+OBD16 engines onward among the codes that justify replacing the sensor, whereas supply-voltage and communication codes point elsewhere. No public threshold exists. P24B5/P24B6 are plain heater circuit shorts, P24B7 the heater resistance. A sensor that cannot heat cannot burn off soot, so filter monitoring stops.
P24FC at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.3 to 1.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P24FC
- Warning lamp
- No soot reading from the PM sensor, DPF monitoring not completed
Common causes of P24FC
- Most likelyInternal failure of the smart PM sensor (heater or electronics)
- PossibleWater ingress cracking the ceramic element or shorting the heater
- Less likelyUnusually high exhaust temperature at the sensor, e.g. during repeated regenerations
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Particulate matter sensor heaterHeater driver
What each part of P24FC means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| FC | The exact fault in that area. |
What to do next
- Note P24FC and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P24FC
What does P24FC mean?
P24FC means "Particulate Matter Sensor Heater Control Circuit Driver Current/Temperature Too High". P24FC concerns the output stage that powers the heater of the particulate matter sensor: the driver reports excessive current or an internal temperature past its limit, which suggests a heater with shorted turns or too little resistance, or an overheating sensor electronics unit. It is a generic code, so it means the same on every make.
Is it safe to drive with P24FC?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P24FC fail an emissions test?
Yes, it can. P24FC is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P24FC to fix?
Difficulty: medium. A typical repair takes 0.3 to 1.5 hours of work. This is a job for a workshop.
Will P24FC clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.