Detailed guide for SPN 3146 FMI 4
Back to top ↑Low voltage on SCR outlet temp sensors typically comes from an open circuit before anything mechanical.
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Share ↓SPN 3146 FMI 4Severity: Warning
SPN 3146 FMI 4: SCR outlet temperature sensor voltage low – open circuit
Quick Answer
SCR outlet temperature sensor voltage low – open circuit
Code
SPN 3146 FMI 4
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- SCR outlet temp reads flat
- Aftertreatment logic confused
- Idle feels odd
Likely Causes
- Open circuit
- Poor sensor ground
- Connector pin issue
Common Fixes
- Fix wiring open
- Secure grounds
- Replace sensor only if harness is good
Full technical sections↓
What does SPN 3146 FMI 4 mean?
Back to top ↑SCR outlet temperature sensor voltage low – open circuit
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