This is an old post but I just read about someone having this exact same problem and a very helpful fix posted by Tony Sovis, a very experienced Kubota tech on a Kubota facebook group.
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Tony Sovis
If you look at the back of the tractor in the left side, mounted near the left rear tire are 2 relays. To get you going, apply heat from a blow dryer or heat gun and the code will go away. The contacts inside the relay are sticking, not allowing them to move when the key is turned and supply power to the ECU, giving you that code. I've also had luck just leaving the key on for a few minutes and it will unstick itself. I've only had this happen on machines that are outside, I believe moisture gets in the relay abs freezes.
Original post of Author with problem
Tony Sovis thanks!
Tony Sovis
I'd bet dollars to donuts that is your issue. I'm not sure if Kubota changed the part numbers, but I would replace those relays when you have time. Sometimes just leaving the key on is enough to create the heat to get the contacts to close, code goes away, tractor will start.
Original post of Author with problem
Tony Sovis it worked thanks!
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