Pull up to the ramp, 28 degrees, raise the motor and remove transom saver and that's the last sign of life from the cranking battery. Tried the trolling motor and it worked fine, but there was nothing from the big battery. Went to an automotive shop near the lake and the cranking battery checked out fine. Came back to the house and after a few hours in the sun and about 38 degrees everything worked fine. Not sure what to think or what to troubleshoot.