Have a Helix 9 about 6 months old and never had a problem, went out fishing this morning and everything was good for about a hour then it would say "Shutting Down" which it did. It would always turn back on and work but just for about 15-30 seconds then shut down again. Any Ideas???

Most likely power issue. Make sure the battery is good along with good connections. Also its always best to run power leads directly to the battery with with a fuse on the "+" lead. Avoid wiringvto existing boat fuse panel or wiring harness

I'll try that thanks. I was thinking if it was a wiring issue it would just turn off, and not tell me that it was shutting down.

You are losing voltage somewhere causing the issue of the unit shutting down.

My H7 does the same thing, if I turn it off before cranking the outboard I can turn it back on no problem. If I forget to turn it off and crank the outboard, I can kill master power and turn it back on. How is that? The power wire running to the front goes to a switch with a split butt splice is this the problem. What's the minimum voltage?

My Helix 7 started doing the same thing a few days ago. Definitely a power issue. When I would start the engine, the Helix would turn off and not turn on again. Voltage loss?
Strangely, when I would pull out the fuse and reinstall it, the unit would work after hitting the on button. I had it wired to the engine starting battery.
I switched the wires to an designated battery with nothing else wired to it. No more problems. I charge the designated battery after each use.
Nuisance having an additional battery on board, but it eliminates all interference too.

Anytime I've had a problem with my fishfinder turning off or acting funny it was the battery or the connection. I use a 12 volt deer feeder battery. When It gets under 10 volts it needs recharged

I would suggest wiring graphs directly to battery. Won�t happen again. You are always going to loose voltage going through an accessory switch.