2020 Kubota with Kaw FR651v, 80 hrs. I have a constant 12v draw at regulator, even with key turned off. I am pretty sure it should be zero with key off. Can you point me to the test procedure for the ignition switch? What else might send voltage to the regulator? It runs fine and is charging the battery when it is running but has been dead the last couple times I went to use it. I run it for about an hour every week. Does not drain the battery if I disconnect the regulator B+ wire.
Next time you use the unit, run at full throttle and tell us what voltage you have. After you have completed your work shut it down and measure battery voltage, unit off. When you post back give us the model and serial numbers for the unit.