Cylinder #5 Injector - Current Below Normal (Open Circuit)
The JD-SPN655-FMI5 (John Deere PowerTech) diesel fault code means: Cylinder #5 Injector - Current Below Normal (Open Circuit). This is a serious severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
- Estimated cost
- $250-$800 injector
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Common Symptoms
- Cyl 5 misfire (6-cyl engines: 6.8L, 9.0L, 13.5L)
- Rough idle, loss of pull
Probable Causes (Ranked by Likelihood)
- Harness break / chafed wire Very Likely
- Failed injector Likely
Frequently Asked Questions
What is John Deere fault code SPN 655 FMI 5?
On John Deere PowerTech engines, SPN 655 FMI 5 means: Cylinder #5 Injector - Current Below Normal (Open Circuit). Serious code -- address promptly to avoid inducement / further damage.
Can I keep using my John Deere tractor with SPN 655 FMI 5?
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 655 FMI 5?
Repair cost range: $250-$800 injector. Dealer labor on large tractors runs $180-$240/hr in 2026.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
Service ADVISOR cylinder balance test; verify by swapping injectors.
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)
Commonly Affected Vehicles
- 2014+ John Deere 6R Series tractors
- 2015+ John Deere 7R Series tractors
- 2015+ John Deere 8R / 8RT Series tractors
- 2015+ John Deere 9R / 9RT / 9RX Series tractors
- 2015+ John Deere S670 / S680 / S690 combines
- John Deere S770 / S780 / S790 combines
- John Deere 544/644/724 wheel loaders (construction)
- John Deere 310/410 backhoes
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