Detailed guide for MID 128 PID 81 FMI 5
Back to top ↑MID 128 PID 81 FMI 5 - Particulate Filter
**Fault Type:** Current below normal or open circuit
Fault Condition
- Open in 5 volt supply line
- Short to ground in metering line
- Open in metering line
Possible Symptoms
- Malfunction indicator lamp illuminated
Possible Causes
- Particulate Trap Pressure (PTP) Sensor failure
- Faulty harness
Diagnostic Tips
1. Check for open circuits in sensor power (5V), ground, and signal wires
2. Inspect for shorts to ground in signal circuit
3. Verify 5V reference at sensor connector with key on
4. Check continuity of wiring between sensor and ECU
5. Inspect connector pins for damage or corrosion
Mechanic community notes for MID 128 PID 81 FMI 5
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