John Deere 644: Lead ECU Sync Circuit Fault

The fault code indicates an issue with the Lead ECU Sync Circuit. This may affect the communication or synchronization between the main control unit and the lead ECU.

1. 1

   The wiring and connections of the Lead ECU Sync Circuit

2. 2

   The integrity of the signal path between the main control unit and the lead ECU

1. 1

   Inspect the wiring and connections

   Check for any damage, loose connections, or corrosion in the wiring and connections of the Lead ECU Sync Circuit.

2. 2

   Test the signal path

   Use a diagnostic tool to verify the signal path between the main control unit and the lead ECU.