Detailed guide for MID 128 PID 102 FMI 3
Back to top ↑MID 128 PID 102 FMI 3 - Boost Pressure Sensor High Voltage
**Technical Details**: This fault triggers when voltage on the signal circuit exceeds 4.95V [citation:2]. The Intake Manifold Pressure Sensor (often combined with temperature sensor) is located in the intake manifold.
🔌 Electrical Diagnosis
**Step 1 - Visual Inspection**
- Check connector for corrosion, bent pins, or damaged seals
- Look for chafed wires near the intake manifold (heat and vibration)
**Step 2 - Voltage Tests**
- Key ON, engine OFF
- Backprobe signal wire at sensor—should read 0.5-1.0V (atmospheric pressure)
- If reading is 5V or higher, problem exists
**Step 3 - Sensor vs Wiring**
- Disconnect sensor
- Check signal voltage at harness side
- If still 5V+, you have short to reference or power
- If voltage drops to 0V, sensor may be faulty
📊 Sensor Specs
Volvo MAP sensors typically output:
- 0.5V at 40 kPa (atmospheric, ~14.7 PSI absolute)
- 4.5V at 400 kPa (58 PSI absolute) [citation:2]
🖼️ Image Resources
- "MAP sensor location Volvo D13" (search YouTube screenshots, fair use)
- "Automotive sensor voltage testing" (generic multimeter usage)
💡 Tech Tip
*"On Volvo D13 engines, the MAP sensor harness runs near the back of the intake manifold. Heat over time makes the insulation brittle, and wires can short together. Always inspect this area thoroughly."* — Volvo dealer tech

Mechanic community notes for MID 128 PID 102 FMI 3
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