ST60 Raymarine sounder stops working

[Ricchezza]

Help needed, please!

I am navigating and the sound stops working.
The transducer in the water we dove and clean it up, there has been some litte shells.
We noticed one day before, after a heavy rain, water on one of the fixing screws at the backside. Well, but it worked then.
Now 1 day later, starting it was flashing is last depth (ok, this really has been the depth before) and then nothing.
Pushing depth-button cause at the display shown lamps and continuing pushing it showd contrast
????
I used some contact spray, no change.
Is there any waynin the water to check-out if it comes from the sounder or the instrument?
Do you think tha water can really enter in this instrument?

Many thanks for all advices!