Blank screen on down imaging

[sbleifus]

I have a mega 12si, when I go to the down imaging screen, there are just little dots, no images. Most of the screen is black. Everything else seems to work fine.

[Greenwing1]

Are you using 2 transducers with a y cable?

[ezfishn]

Might try resetting defaults and if that doesn't correct the problem then verify you are using the correct y-cable.

https://www.humminbird.com/faqDetail.aspx?id=16892

[sbleifus]

Thanks. I think I'm using the wrong cable