Cylinder #1 Injector - Current Below Normal (Open Circuit)
The JD-SPN651-FMI5 (John Deere PowerTech) diesel fault code means: Cylinder #1 Injector - Current Below Normal (Open Circuit). This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $250-$650 injector, $60-$220 valve-cover harness
A $30 car code reader can't do diesel. The HD7000 reads full-system codes and does parked DPF regen, idle/speed-limit, and service resets from the cab — on everything from a 6.7 Cummins/Power Stroke/Duramax pickup to Class-8 trucks (Detroit, Paccar, CAT, Volvo, Mack, International).
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Full-system 6/9/16-pin diesel scan tool for Cummins, Paccar, CAT, Detroit and more — plug-and-play, no subscription. A cheaper way to read heavy-duty codes a basic OBD2 scanner skips entirely.
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Common Symptoms
- Rough idle / misfire on cylinder 1
- White smoke on cold start
- Loss of rated PTO power
Probable Causes (Ranked by Likelihood)
- Broken injector solenoid wire at valve-cover pass-through (common) Very Likely
- Failed injector solenoid Likely
- ECU injector driver fault Less Likely
Step-by-Step Diagnostic Procedure
Pull valve cover and inspect injector wiring harness pass-through -- chafe points are normal.
Swap injector from another cylinder and recheck if code moves with injector.
Run injector electrical test in Service ADVISOR.
Frequently Asked Questions
What is John Deere fault code SPN 651 FMI 5?
On John Deere PowerTech engines, SPN 651 FMI 5 means: Cylinder #1 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 651 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 651 FMI 5?
Repair cost range: $250-$650 injector, $60-$220 valve-cover harness. Dealer labor on large tractors runs $180-$240/hr in 2026.
Sources
This page is built from documented references. Verify against your own service info before repair work.
SPN651-FMI5 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: