P24C8 code meaning
Particulate Matter Sensor Temperature Circuit Low
Powertrain system Generic code P24xx codes Check engine light
What P24C8 means
P24C8 would be set when the temperature signal of the particulate matter sensor sits below its valid range, for example because the meander line is shorted to ground. No manufacturer documents this code publicly; the available summaries fold low and high readings into other codes. Ford's 2023 diesel summary reports any reading under 0.3 V as P24C6, and GM's 25OBDG04A table includes values under 0.3 V in its P24C9 check. CARB requires PM sensor circuits to be checked for out-of-range values, so a low-side code is the logical place for such a fault. Expect a damaged sensor pigtail, a pinched harness or water in the connector. Without a temperature value the heater cannot be regulated and the filter monitor stays inactive. P24C9 is the high counterpart.
P24C8 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairAfter a drive cycle
Symptoms of P24C8
- Malfunction indicator lamp on
- Particulate filter monitor does not complete
Common causes of P24C8
- Most likelyTemperature line shorted to ground
- PossibleWater in the sensor connector
- PossibleInternal fault of the sensor element
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Particulate matter sensor
What each part of P24C8 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). |
| C8 | The exact fault in that area. |
What to do next
- Note P24C8 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 P24C8
What does P24C8 mean?
P24C8 means "Particulate Matter Sensor Temperature Circuit Low". P24C8 would be set when the temperature signal of the particulate matter sensor sits below its valid range, for example because the meander line is shorted to ground. It is a generic code, so it means the same on every make.
Is it safe to drive with P24C8?
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 P24C8 fail an emissions test?
Yes, it can. P24C8 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 P24C8 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P24C8 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.