John Deere 655.05 – Engine Control Unit (ECU): Injector Number 5 Circuit Has High Resistance

The Engine Control Unit (ECU) has detected abnormally high resistance in the electrical circuit of the fuel injector for cylinder number 5. This indicates a problem with the injector's internal coil or the wiring and connections leading to it. This condition can prevent the injector from opening correctly, leading to fuel delivery issues in that cylinder, which may cause engine misfires, rough running, loss of power, or difficulty starting.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 5065M
• 5075M
• 7185J
• 7195J
• 7205J
• 7210J
• 7225J
• 7720
• 7820
• 7920
• 7930
• 8130
• 8230
• 8330
• 8225R
• 8235R
• 8245R
• 8260R
• 8270R
• 8285R
• 9200
• 9300
• 9400
• 9470RT
• 9520RT
• 9570RT
• 444J
• 544J
• 624J
• 744H
• 160GLC
• 180GLC
• 210G
• 335D
• 350DLC
• 350GLC
• 380GLC
• E330LC
• E360
• E400
• 670G
• 672G
• 770G
• 772G
• 870G
• 872G
• 753J
• 759J
• 803M
• 853M
• 903K
• 909K
• 1270E
• 1470D

1. 1

   Restart the engine to verify if the active Service Code reappears, ruling out a temporary communication glitch.

2. 2

   Inspect the electrical connector at the cylinder #5 injector for loose pins, corrosion, or physical damage.

3. 3

   Use a multimeter to test the wiring harness for an open wire in the 90V supply / EUI control wire between the Engine ECU and the injector.

4. 4

   Measure the resistance across the terminals of the cylinder #5 injector solenoid to check for an open circuit inside the injector.

1. 1

   Turn off the engine, disconnect the battery, and allow the engine to cool.

2. 2

   Locate the cylinder #5 fuel injector and carefully disconnect its electrical connector.

3. 3

   If the diagnostic tests proved the wiring harness is faulty, repair the broken wire or replace the affected harness section.

4. 4

   If the injector solenoid failed the resistance test, clean the area around the injector to prevent debris from entering the engine.

5. 5

   Remove the high-pressure fuel line connecting the common rail to cylinder #5.

6. 6

   Remove the injector hold-down clamp and carefully extract the faulty injector.

7. 7

   Install the new OEM injector using a new injector install kit (new O-rings and seals).

8. 8

   Reinstall the injector hold-down clamp and torque to OEM specifications.

9. 9

   Install the high-pressure fuel line and torque the fittings.

   It is often recommended to replace the high-pressure fuel line when replacing an injector to prevent contamination or leaks.

10. 10

    Reconnect the electrical connector.

11. 11

    Reconnect the battery, clear the fault codes from the ECU, and run the engine to verify the repair.

    Depending on the engine model, the new injector's calibration QR code may need to be programmed into the ECU using a diagnostic tool.