P24D3Reductant Heater B Sense Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P24D3 is the same kind of fault for heater B, which GM and Ford assign to the heated DEF line from pump to dosing valve. The read-back line of this heater is broken or delivers nonsense, so the controller cannot tell whether the hose is really powered; the narrower low and high cases are P248C and P248D. No manufacturer documents P24D3 in this sense. FCA uses the number differently: bulletin 18-008-23 for 2019 Jeep Compass diesels outside North America lists P24D3-00 as a particulate matter sensor supply voltage above threshold, fixed with new PCM software. GM's diesel tables from 2016 to 2018 describe a line heater sense check with a 3 V limit. A line that does not thaw blocks dosing in winter, so the fault deserves attention before frost.
- What you may notice
- Malfunction indicator lamp on
- DEF dosing faults or warnings at low temperatures
- Likely causes
- LikelyOpen sense wire or loose plug at the heated DEF line
- PossibleDamaged heated line with internal conductor fault
- RareManufacturer-specific use of the code (FCA uses it for PM sensor supply), software update
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.