Powertrain, generic (extended)

P24C8 Particulate Matter Sensor Temperature Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

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.

Likely causes

Temperature line shorted to ground
Water in the sensor connector
Internal fault of the sensor element

Symptoms

  • Malfunction indicator lamp on
  • Particulate filter monitor does not complete

Repair estimate

DifficultyMediumDIY possible
Parts and labour€100–700
Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

particulate matter sensor

Related codes

P24C6P24C7P24C9P24CA

References: law.cornell.edu, fordservicecontent.com, gsi.ext.gm.com.