Detailed guide for SPN 108 FMI 3
Back to top ↑Baro sensors help the ECM adjust fuel mix as altitude changes. If voltage spikes, readings make the ECU think it’s higher than reality.
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Share ↓SPN 108 FMI 3Severity: Warning
SPN 108 FMI 3: Barometric pressure sensor voltage high – altitude reading error
Quick Answer
Barometric pressure sensor voltage high – altitude reading error
Code
SPN 108 FMI 3
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- Power change at altitude
- Incorrect fuel trim
- Idle variations
Likely Causes
- Short to power
- Loose harness
- Connector corrosion
Common Fixes
- Check sensor harness
- Secure clipping points
- Replace sensor if verified faulty
Full technical sections↓
What does SPN 108 FMI 3 mean?
Back to top ↑Barometric pressure sensor voltage high – altitude reading error
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