Detailed guide for SPN 3364 FMI 3
Back to top ↑High sensor voltage means the circuit may be getting power it shouldn’t, often due to corrosion or a cut harness. This doesn’t always mean the DEF fluid is bad, so verify wiring first.
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Share ↓SPN 3364 FMI 3Severity: Warning
SPN 3364 FMI 3: DEF quality sensor voltage high – possible short to power
Quick Answer
DEF quality sensor voltage high – possible short to power
Code
SPN 3364 FMI 3
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- DEF quality alert
- May lead to false quality failure
- DEF dosing interrupted
Likely Causes
- Short to power
- Corroded connectors
- Sensor internal fault
Common Fixes
- Inspect wiring for shorts
- Clean/repair connectors
- Replace sensor if necessary
Full technical sections↓
What does SPN 3364 FMI 3 mean?
Back to top ↑DEF quality sensor voltage high – possible short to power
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