Detailed guide for SPN 3146 FMI 3
Back to top ↑Temperature sensors in SCR help the ECM decide restart/reduce emissions load. High voltage usually means wiring faults rather than scorch conditions.
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Share ↓SPN 3146 FMI 3Severity: Warning
SPN 3146 FMI 3: SCR outlet temperature sensor voltage high – heater circuit issue
Quick Answer
SCR outlet temperature sensor voltage high – heater circuit issue
Code
SPN 3146 FMI 3
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- SCR temps too warm
- Aftertreatment light
- Possible derate later
Likely Causes
- Short to power
- Connector corrosion
- Sensor heat soak
Common Fixes
- Dry connectors
- Repair wiring
- Replace sensor
Full technical sections↓
What does SPN 3146 FMI 3 mean?
Back to top ↑SCR outlet temperature sensor voltage high – heater circuit issue
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