Detailed guide for MID 128 PID 81 FMI 12
Back to top ↑MID 128 PID 81 FMI 12 - Particulate Filter
**Fault Type:** Bad intelligent device or component
Fault Condition
- Particulate Trap Pressure (PTP) Sensor signal high or low but still within range
Possible Symptoms
- Engine derate
- Malfunction indicator lamp illuminated
Possible Causes
- Diesel Particulate Filter (DPF) is damaged
- DPF is filled with soot
- DPF is missing
- Sensor signal out of expected range but within electrical limits
Diagnostic Tips
1. Visually inspect DPF for physical damage or missing components
2. Check if DPF has been removed or tampered with
3. Verify soot and ash loading levels with diagnostic tool
4. Check for exhaust leaks before or after DPF
5. Inspect for cracks in DPF housing
6. Verify proper regeneration has been occurring
7. Check Differential Pressure DPF Sensor readings at idle and under load
Mechanic community notes for MID 128 PID 81 FMI 12
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