2017 DF300 "Low battery voltage" 0.0 volts

[Cdenovan]

Hi, had an intermittent problem where I would turn the isolators on and the display would show 0 volts, although the motor would crank over, but not start or trim/tilt at the throttle or engine trim switches. The batteries are perfect.
Then it might read 12.8 and run as normal without doing anything.
I broke down at sea and it had been throwing up 2-4 codes randomly too. I've never managed to get the display unit to read anything but 0 now.
I've checked the white wire connection on the battery, fuse and as far as I can see going into the loom without peeling off the tape.
any ideas?
Thanks

[artdf175]

Just a thought-- this could e a ground wire problem
suggestion - check battery posts make sure they are clean
and then find the ground bar and check that for corrosion

[Cdenovan]

I eventually found the problem. Towards the end of the long part of the wiring harness, before it meets the outboard connection, there was a split in the white wire, hidden by the webbing. I pulled it back and was over the moon to see the blue-ish residue of dissolving copper. It had been throwing up 2-4 codes and shift control unit error messages randomly. I'm hoping that was the cause.
Thanks for your reply.