John Deere Engines SPN1076FMI5 Fault Code: Pump Solenoid Circuit Open
Pump Solenoid Circuit Open · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
SPN 1076 FMI 5 means the ECU has detected an open circuit in the injection pump solenoid control loop. This is the Stanadyne DE10 injection pump solenoid circuit. When this code sets, the engine will not run and the red stop lamp comes on. This is a stop-now condition since the engine cannot operate until the circuit is repaired.
Critical severity. The engine does not run when this code sets, and the red stop lamp comes on. There is no partial-function or limp mode described, so this is a no-start condition that must be resolved before the engine can be operated.
What does John Deere Engines error code SPN1076FMI5 mean?
SPN 1076 FMI 5 points to the pump solenoid circuit being open. On engines using the Stanadyne DE10 injection pump, the pump has an internal solenoid controlled by the ECU. The ECU switches current on and off to charge this solenoid, and by managing that current it moves a pump control valve that either allows or ends injection pressure. In short, the ECU uses this solenoid circuit to control how much fuel is delivered and when.
When the ECU sees the solenoid circuit as open rather than a complete, working circuit, it cannot control the pump's timing valve. Since the ECU has no way to manage fuel delivery through an open circuit, the safest response built into the system is to stop the engine from running and light the red stop lamp.
Common causes of SPN1076FMI5
- Bad terminals or connector at the ECU
- Bad terminals or connectors at the pump
- Open or short in the circuits running to the pump solenoid
- Bad fuel pump solenoid
- Bad pump
- Bad ECU
How to troubleshoot John Deere Engines SPN1076FMI5: first checks
- Disconnect the ECU and pump connectors and inspect terminals for corrosion, looseness, or damage before testing anything electrically.
- With connectors disconnected, measure resistance from ECU-K2 to pump A and from ECU-A3 to pump B. Both readings should be less than 0.5 ohms; if either is off, look for an open wire in that circuit.
- Measure resistance from ECU-K2 to chassis. This should read greater than 100K ohms (essentially open/infinite). If it reads lower, the wire is shorted to ground somewhere and needs to be traced and repaired.
- Measure resistance from ECU-A3 to chassis ground. This should be less than 0.5 ohms. Remember the ECU ground connection should go to the battery only, not a random chassis point.
- At the pump valve connector, measure resistance from A to B. It should be greater than 0.5 ohms and less than 5 ohms. Outside that range, the valve itself needs replacement.
- If all wiring and valve resistance checks pass but the engine still will not start, confirm fuel flow to the pump from the supply pump. Good supply flow with no start points toward the high pressure pump needing replacement.
- Double-check that wires are reconnected to the correct terminals before and after testing; a swapped terminal can look like an open circuit.
How the code clears
No separate clearing step is listed. Once the open circuit is located and repaired, whether it is a bad connector, an open or shorted wire, a bad solenoid, a bad pump, or in rare cases a bad ECU, the code should clear on its own once the ECU sees a properly closed and correctly resistive circuit again.
Frequently asked questions
What does SPN 1076 FMI 5 mean on a John Deere engine?
It means the ECU has detected that the pump solenoid circuit, which controls the Stanadyne DE10 injection pump's internal timing solenoid, is open rather than complete. The engine will not run and the red stop lamp comes on.
Why won't my engine start with this code?
The ECU manages fuel quantity and timing by controlling current to the pump solenoid. With the circuit open, the ECU has no way to move the pump control valve, so it will not allow the engine to run.
What resistance readings should I expect when testing this circuit?
From ECU-K2 to pump A and ECU-A3 to pump B, you should read less than 0.5 ohms. ECU-K2 to chassis should read greater than 100K ohms, and ECU-A3 to chassis ground should be less than 0.5 ohms. At the pump valve connector, A to B should read between 0.5 ohms and 5 ohms.
Could this code be caused by something other than wiring?
Yes. Possible causes include bad terminals or connectors at either the ECU or the pump, an open or short in the wiring, a bad fuel pump solenoid, a bad pump, or, less commonly, a bad ECU.
If the wiring and valve test fine, what's next?
Confirm the supply pump is delivering good fuel flow to the injection pump. If fuel supply is good and the engine still won't start, the high pressure pump likely needs replacement.
Is it safe to keep trying to start the engine with this code active?
Repeated crank attempts without diagnosing the open circuit won't damage anything extra beyond normal starter wear, but the engine will not run until the fault is fixed, so it's better to move straight into the connector and resistance checks.
Do I need special tools to diagnose SPN 1076 FMI 5?
A basic digital multimeter capable of reading resistance is enough to perform all the checks: disconnecting the ECU and pump connectors, then testing wire and valve resistance as described.