Question for you vets. I have an old Beaver Contessa (1990). I've had it for many years and never a (major) issue. I just installed (2) new battery's and I recently took a 250 mile trip with zero prob...
No, only should be shut off when in storage. When plugged in the charger should keep them topped off. Make sure the breakers and fuses for the charger have not tripped.