John Deere 653.06 – Engine Control Unit (ECU): Injector Number 3 Low Resistance Error

The control module has detected an abnormally high current draw or a short circuit (low resistance) in the electrical circuit for the #3 cylinder's electronic unit injector (EUI).

• 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
• 6120-6420
• 6230
• 6330
• 6430
• 7610
• 7710
• 7810
• 7630
• 7730
• 7830
• 7930
• 8330
• 9230-9630 series
• 6M series
• 750J
• 850J
• 444J
• 544J
• 624J
• 130G
• 160GLC
• 180GLC
• 250GLC
• 1070E
• 1170E
• 4930

1. 1

   Cycle the power by restarting the engine to verify if the active code reappears, ruling out a temporary communication glitch.

2. 2

   Inspect the engine wiring harness between the ECU and the #3 injector for chafed wires, melted insulation, or pinched lines that could cause a short circuit to ground or to another wire.

3. 3

   Disconnect the #3 injector and use a multimeter with a proper connector adapter test kit to measure the resistance across the injector solenoid pins. Compare to OEM specifications (near zero indicates an internal short).

1. 1

   Safety First

   Turn off the engine, disconnect the battery, and allow the engine to cool. Relieve fuel system pressure before opening any lines, as high-pressure fuel can penetrate the skin and cause severe injury.

2. 2

   Access the Injector

   Depending on the engine model (e.g., 10.5L/12.5L), the electronic unit injectors may be located under the engine valve cover. Remove the valve cover if necessary.

3. 3

   Isolate the Fault

   Disconnect the electrical connector at the #3 injector. Test the harness side for shorts. If the harness is damaged, repair or replace the engine wiring harness. If the harness tests good, the injector itself has failed.

4. 4

   Replace the Injector

   Remove the hold-down clamp and extract the faulty #3 injector. Clean the injector cup/bore thoroughly.

5. 5

   Install New Injector

   Install the replacement injector with new O-rings. Torque the hold-down bolt to exact OEM specifications.

6. 6

   ECU Calibration

   Reconnect the wiring and battery. Use a diagnostic tool (like John Deere Service ADVISOR) to program the new injector's calibration QR code/trim code into the ECU to prevent secondary fault codes and poor engine performance.

7. 7

   Test

   Clear the ECU fault codes, prime the fuel system, and test-run the engine to verify the repair.