Detailed guide for MID 128 PID 81 FMI 0
Back to top ↑MID 128 PID 81 FMI 0 - Particulate Filter
**Fault Type:** Data valid but above normal operational range - most severe level
Fault Condition
- Moderately high pressure detected in Diesel Particulate Filter (DPF)
Possible Symptoms
- Engine derate
- Malfunction indicator lamp illuminated
Possible Causes
- Particulate Trap Pressure (PTP) Sensor failure
- DPF may be clogged with soot or ash
- Regeneration may be inhibited or not occurring
Sensor Information
The Differential Pressure DPF Sensor is located on the side of the Diesel Particulate Filter (DPF). This sensor has two pressure ports and senses the difference in pressure before and after the DPF, which is used to calculate diesel filter regeneration needs.
Diagnostic Tips
1. Check DPF pressure sensor readings with diagnostic tool
2. Inspect DPF for excessive soot accumulation
3. Check if regeneration has been inhibited or disabled
4. Verify pressure sensor tubing is not blocked or damaged
5. Check for exhaust leaks before or after DPF that could affect readings
6. Monitor soot loading levels with Premium Tech Tool (PTT)
Mechanic community notes for MID 128 PID 81 FMI 0
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