Detailed guide for SPN 102 FMI 4
Back to top ↑Low voltage on the boost signal usually means wiring or a dead sensor.\n\nIf it’s intermittent, suspect a loose pin or rub-through.
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Share ↓SPN 102 FMI 4Severity: Warning
SPN 102 FMI 4: Boost pressure voltage low – open circuit/short to ground
Quick Answer
Boost pressure voltage low – open circuit/short to ground
Code
SPN 102 FMI 4
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- MIL on
- Reduced power
- Boost reads low or zero
Likely Causes
- Open signal wire
- Short to ground
- Sensor failure
Common Fixes
- Check wiring continuity and grounds
- Repair harness routing
- Replace sensor if wiring is good
Full technical sections↓
What does SPN 102 FMI 4 mean?
Back to top ↑Boost pressure voltage low – open circuit/short to ground
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