I installed a BMV 712 on my sailboat as part of a Battery Management system two years ago. I just returned from a trip and went to the boat and the unit is not working. It is on and shows a code. I have attached a picture with the code. None of the buttons on the front will work and I cannot connect with Bluetooth. An Electronics friend took it hope and bench tested it with no better results. Has it failed? If so, what might have happened. The boat has been at my marina in the US with AC shore power applied the entire time. The batteries are all fine.