Detailed guide for SPN 4795 FMI 31
Back to top ↑Usually shows up after aftertreatment work when the ECM decides the hardware does not match expectations.\n\nFix the mismatch. Clearing it will not make the system forget.
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Share ↓SPN 4795 FMI 31Severity: Critical
SPN 4795 FMI 31: DPF missing condition exists (hardware/config mismatch)
Quick Answer
DPF missing condition exists (hardware/config mismatch)
Code
SPN 4795 FMI 31
Severity
Critical
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- Immediate aftertreatment fault
- May derate quickly
- Often appears after exhaust work
Likely Causes
- Hardware does not match calibration
- Sensors routed incorrectly
- Aftermarket component mismatch
Common Fixes
- Verify aftertreatment hardware matches calibration
- Check sensor hookups and orientation
- Correct mismatch before clearing codes
Full technical sections↓
What does SPN 4795 FMI 31 mean?
Back to top ↑DPF missing condition exists (hardware/config mismatch)
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