Detailed guide for SPN 2799 FMI 7
Back to top ↑If the pump won’t respond, the system is dead in the water.\n\nWinter freeze damage is a very common root cause.
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Share ↓SPN 2799 FMI 7Severity: Critical
SPN 2799 FMI 7: DEF pump not responding – pump does not follow command
Quick Answer
DEF pump not responding – pump does not follow command
Code
SPN 2799 FMI 7
Severity
Critical
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- Inducement risk
- DEF pressure flat
- SCR efficiency drops
Likely Causes
- Pump seized or damaged
- Frozen DEF damage
- Electrical command issue
Common Fixes
- Confirm heaters and line temps (winter)
- Check pump command and feedback
- Replace pump if it cannot respond
Full technical sections↓
What does SPN 2799 FMI 7 mean?
Back to top ↑DEF pump not responding – pump does not follow command
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