Average Fuel Economy (mpg or L/hr) - Condition Exists
The JD-SPN185-FMI31 (John Deere PowerTech) diesel fault code means: Average Fuel Economy (mpg or L/hr) - Condition Exists. This is a moderate severity code.
Unverified. We could not confirm this code's definition against freely available manufacturer documentation, so treat the meaning, severity and fix guidance on this page as unconfirmed. Check it against the manufacturer's service information for your exact model and serial range before acting on it. This page is kept out of search engines for that reason, and we are working through this family manual by manual.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $0-$180 software / operator-guide update
What Are the Symptoms of JD-SPN185-FMI31?
- Informational code -- no power loss
- Data-logging / telematics warning on JDLink
What Causes JD-SPN185-FMI31? (Most Likely First)
- Stale or missing configuration parameter Likely
- Historical over-range event already resolved Likely
- GPS / CAN broadcast mismatch Possible
Can I Still Drive with JD-SPN185-FMI31?
Yes, but fix soon. JD-SPN185-FMI31 is rated moderate severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring it.
Frequently Asked Questions
What is John Deere fault code SPN 185 FMI 31?
On John Deere PowerTech engines, SPN 185 FMI 31 means: Average Fuel Economy (mpg or L/hr) - Condition Exists. Moderate code -- diagnose soon; continued operation may increase repair scope.
Can I keep using my John Deere tractor with SPN 185 FMI 31?
Moderate fault -- you can usually keep working but expect derate if aftertreatment-related. Diagnose with John Deere Service ADVISOR via an EDL v3 / CF3 interface.
How much does it cost to fix John Deere SPN 185 FMI 31?
Repair cost range: $0-$180 software / operator-guide update. Dealer labor on large tractors runs $180-$240/hr in 2026.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose JD-SPN185-FMI31?
Verify current configuration vs. dealer PIP update.
Clear the code; if it does not return after 10 engine hours, consider resolved.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J1939-73Application Layer: Diagnostics (defines the SPN/FMI fault-identifier framework)
Which Vehicles Commonly Get JD-SPN185-FMI31?
- 2015+ John Deere 7R Series (7210R, 7250R, 7290R, 7310R)
- 2015+ John Deere 8R / 8RT Series (8245R-8370R)
- 2015+ John Deere 9R / 9RT / 9RX Series (9370R-9620R)
- John Deere S670 / S680 / S690 combines
- John Deere S770 / S780 / S790 combines
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