Detailed guide for SPN 3515 FMI 4
Back to top ↑Voltage low is almost always wiring or a dead sensor.\n\nIf it appeared after service, check what got tugged.
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Share ↓SPN 3515 FMI 4Severity: Warning
SPN 3515 FMI 4: EGR differential pressure voltage low – open circuit/short to ground
Quick Answer
EGR differential pressure voltage low – open circuit/short to ground
Code
SPN 3515 FMI 4
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- MIL on
- EGR flow readings stuck low
- EGR faults stack quickly
Likely Causes
- Open circuit wiring
- Short to ground
- Sensor failed
Common Fixes
- Check continuity and 5V reference
- Repair wiring and secure routing
- Replace sensor if circuit is good
Full technical sections↓
What does SPN 3515 FMI 4 mean?
Back to top ↑EGR differential pressure voltage low – open circuit/short to ground
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