Isx shutting off randomly

[JimT]

I'd agree with Signature620. Either keyswitch or some other wiring between the batteries and the ignition. Might want to start at the batteries, test all of them, clean up the connections, check all the cables (and grounds) then work your way toward the ignition. Replace any fuses, in-line and in fuse box, related to it.

Pay close attention to you battery cables. One time I had one corrode inside the lug, hidden there until it presumably fell out after hitting a bump and bounce around inside my aluminum battery box. The shorting caused similar dashboard issues as you mentioned. It was subtle and intermittent and took some really close inspection to find the cause. Probably also the reason I had to replace all my batteries again after only 1 year.