John Deere 651.06 – ECU: Injector Number 1 Circuit Has Low Resistance

The engine controller has detected that the electrical resistance in the circuit for the cylinder #1 fuel injector has dropped below the expected threshold, indicating a short circuit to ground within the wiring harness or an internal short inside the injector's solenoid.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5065M
• 5075M
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5095M
• 5095MH
• 5105M
• 5015ML
• 5090M
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6105D
• 6120-6420 series
• 7630-7930 series
• 9230-9630 articulated tractors
• 310K
• 444J/K
• 544J/K
• 624J/K
• 710K
• 700K
• 750J/K
• 850J/K
• 130G
• 160GLC
• 180GLC
• 250GLC

1. 1

   Inspect the wiring harness and connectors leading to the cylinder #1 fuel injector for chafed wires, melted insulation, or exposed copper that could be shorting to the engine block or another wire.

2. 2

   Disconnect the Injector #1 connector and measure the resistance across the two pins on the injector using a digital multimeter. Compare to OEM spec or a known-good injector. A reading near zero indicates an internal short in the solenoid.

3. 3

   With the injector and ECU disconnected, test the wiring harness for continuity to ground. If continuity to ground is present on the signal wire, the harness is shorted.

1. 1

   Power Down

   Turn off the engine, place the machine in park, and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Access the Injector

   Remove any engine covers or valve covers necessary to access the fuel injectors and their wiring harness.

3. 3

   Repair Wiring

   If the diagnostic checks revealed a chafed or shorted wire in the harness, splice in a new section of wire using weather-resistant heat-shrink connectors, or replace the injector harness entirely.

4. 4

   Replace Injector

   If the injector solenoid failed the resistance test, remove the high-pressure fuel line and hold-down clamp for cylinder #1. Extract the faulty injector. Clean the injector bore and install a new injector with new O-rings and copper sealing washers. Torque the hold-down bolt and fuel lines to OEM specifications.

5. 5

   ECU Calibration

   Program the new injector's calibration/trim code into the ECU using a diagnostic scan tool (like John Deere Service ADVISOR).

6. 6

   Clear Codes and Test

   Reconnect the battery, clear the ECU 000651.06 fault code, and run the engine to verify the repair. Check for fuel leaks around the new injector.