Df300 won't run, codes, need help

[Double Actiom]

I have an intermittent problem, comes up sometimes and the motor won't work until we fully shutdown all power for 20mins.

7-4, 8-3 codes ,control comm, shift control

Any ideas what could be causing it? It's worked fine for weeks, no issue, then today on a dive trip it dies again.

[joepizz]

What's the state of your battery(ies)?

What's your battery voltage. I've had similar issues because of a dying battery. It's been said here before but I simply cannot be stressed enough. These engines absolutely hate low voltage or weak batteries.