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MID 128 PID 81 FMI 2Severity: Warning

MID 128 PID 81 FMI 2: Particulate Filter - Signal Erratic (Volvo)

Quick Answer

Particulate Filter - Signal Erratic (Volvo)

Code
MID 128 PID 81 FMI 2
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.

Common Symptoms

  • Malfunction indicator lamp illuminated
  • Particulate trap pressure reading may be intermittent or implausible

Likely Causes

  • Sensor is not rational (erratic output)
  • Particulate Trap Pressure (PTP) Sensor failure

Common Fixes

  • Check sensor connections for looseness or corrosion
  • Inspect wiring for intermittent damage
  • Replace faulty sensor
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What does MID 128 PID 81 FMI 2 mean?

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Particulate Filter - Signal Erratic (Volvo)

Detailed guide for MID 128 PID 81 FMI 2

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MID 128 PID 81 FMI 2 - Particulate Filter

**Fault Type:** Data erratic, intermittent or incorrect

Fault Condition

  • Sensor is not rational (output is erratic or implausible)

Possible Symptoms

  • Malfunction indicator lamp illuminated

Possible Causes

  • Particulate Trap Pressure (PTP) Sensor failure
  • Loose or corroded connections
  • Intermittent wiring issue

Diagnostic Tips

1. Check sensor connector for corrosion or damage

2. Inspect wiring harness for intermittent shorts or opens

3. Monitor sensor signal with diagnostic tool while gently moving wiring

4. Check for water intrusion in sensor connector

5. Verify pressure tubing is not partially blocked or leaking

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