Kubota P2300 – Engine ECU: Spark Coil #1 Primary Open/Short-to-Ground

This fault code indicates that there is a short to ground or an open circuit in the interconnect harness, or an open circuit internal to the primary winding of Ignition Coil #1.

• WG1605
• WG2503
• WG3800
• WG972
• DF972
• DG972

1. 1

   Check battery voltage to ensure it is operating within the required 10.0V to 16.0V range

2. 2

   Visually inspect for loose ignition coil connections directly at Ignition Coil #1

3. 3

   Inspect the interconnect harness between the Engine ECU and Ignition Coil #1 for an open circuit or a short to chassis ground

4. 4

   Measure the DC resistance of the coil's low-voltage primary winding across its positive and negative terminals using a digital ohmmeter to check for an internal open circuit

1. 1

   Turn off the ignition and ensure the machine is in a safe, well-ventilated area.

2. 2

   Disconnect the electrical connector at Ignition Coil #1.

3. 3

   Inspect the connector pins for corrosion, damage, or pushed-out terminals.

4. 4

   Test the harness circuits back to the Engine ECU.

   If a short to ground or an open circuit is found in the wiring, repair or replace the interconnect harness.

5. 5

   Remove the mounting hardware and extract the faulty Ignition Coil #1.

   Perform this step if the harness and voltage supply are verified to be in good working order, indicating the fault lies within the ignition coil itself (internal open).

6. 6

   Install the new OEM replacement ignition coil and secure the mounting hardware.

7. 7

   Reconnect the electrical connector, ensuring it clicks securely into place.

8. 8

   Connect a PC with Kubota Diagmaster software (using the DST-i interface) to the engine ECU.

   Clear the permanent fault code and verify the engine runs without triggering the MIL (Malfunction Indicator Lamp).