edd1974:
Isolater on my man is big red thing under the battery area.
For a while used have keep turning mine and.an off to clear messages.
It never affected the tacho.
Was told by hire place Most tachos thes days have a built in battery incase of power interruptions etc.
That’ll be where I went wrong then.
I’ve not had to isolate my batteries for many years. The last time wasn’t long after I got a truck with a digi-tacho.
Isn’t progress wonderful ? 