Aftertreatment SCR Inlet Temperature - Data Valid but Above Normal Operational Range (Most Severe)
What does JD-SPN4360-FMI0 mean?
The JD-SPN4360-FMI0 (John Deere PowerTech) diesel fault code means: Aftertreatment SCR Inlet Temperature - Data Valid but Above Normal Operational Range (Most Severe). This is a serious severity code.
Common Symptoms
- SCR NOx-efficiency fault, derate within one drive cycle if persistent
- Low tailpipe NOx conversion at operating temp
- Dealer-inducement warnings on Tier 4 Final machines
Probable Causes (Ranked by Likelihood)
- Upstream / downstream NOx sensor drift Likely
- SCR inlet / outlet temperature sensor failure Likely
- SCR substrate poisoning (wrong DEF) or thermal damage Possible
- Exhaust leak upstream of SCR disturbing sensor reading Possible
Step-by-Step Diagnostic Procedure
Record SCR inlet vs. outlet temperature during steady-state high idle.
Use Service ADVISOR SCR efficiency test -- compare to CTM acceptance band.
Inspect clamps / V-bands between turbo and SCR for leaks.
If substrate is damaged, only a full catalyst module replacement will clear the code.
Frequently Asked Questions
What is John Deere fault code SPN 4360 FMI 0?
On John Deere PowerTech engines, SPN 4360 FMI 0 means: Aftertreatment SCR Inlet Temperature - Data Valid but Above Normal Operational Range (Most Severe). Serious code -- address promptly to avoid inducement / further damage.
Can I keep using my John Deere tractor with SPN 4360 FMI 0?
Serious fault -- you can move the machine to a shop but don't run it under load. Diagnose with John Deere Service ADVISOR via an EDL v3 / CF3 interface.
How much does it cost to fix John Deere SPN 4360 FMI 0?
Repair cost range: $260-$780 NOx sensor / SCR temp sensor, $3,500-$7,500 SCR catalyst. Dealer labor on large tractors runs $180-$240/hr in 2026.