Detailed guide for SPN 3362 FMI 31
Back to top ↑This appears when DEF flow is not behaving normally. In winter, frozen lines and crystallized fittings are common.\n\nFix flow and heat first before replacing expensive dosing parts.
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Share ↓SPN 3362 FMI 31Severity: Warning
SPN 3362 FMI 31: DEF dosing unit input lines condition exists (line/flow issue)
Quick Answer
DEF dosing unit input lines condition exists (line/flow issue)
Code
SPN 3362 FMI 31
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- DEF/SCR warnings
- May stack into inducement
- In cold weather it may come and go
Likely Causes
- Frozen DEF in lines
- Restriction or crystallization
- Line heater or connector problem upstream
Common Fixes
- Inspect DEF lines for kinks, leaks, or freeze damage
- Confirm line heaters are working
- Clean crystallized fittings and verify flow
Full technical sections↓
What does SPN 3362 FMI 31 mean?
Back to top ↑DEF dosing unit input lines condition exists (line/flow issue)
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