Detailed guide for SPN 5394 FMI 7
Back to top ↑If the doser will not respond, the system cannot control NOx reduction.\n\nThawing alone does not fix deposits.
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Share ↓SPN 5394 FMI 7Severity: Critical
SPN 5394 FMI 7: DEF doser valve not responding
Quick Answer
DEF doser valve not responding
Code
SPN 5394 FMI 7
Severity
Critical
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- Inducement/derate risk
- Dosing does not respond to command
- SCR efficiency drops
Likely Causes
- Valve stuck
- Crystallization/restriction
- Valve failure
Common Fixes
- Remove and inspect valve for deposits
- Confirm DEF quality and heater operation
- Replace valve if it cannot respond
Full technical sections↓
What does SPN 5394 FMI 7 mean?
Back to top ↑DEF doser valve not responding
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