Bi Data depth

[Mavis]

I have a Raymarine bi data unit showing speed and depth. The depth sounder now hardly ever works, staying on 0.00 for ages then randomly shows a depth reading and then stays on that depth for ages. I have tried wriggling wires, etc but can't sort it. Is there anything I can test to see if it is the transducer or the head.
Thanks

 

[mainmarine]

if you can borrow another transducer and hang it over the side while connected to your display it will prove wether it is the display or not.
If you can't find one locally I'm coming down to Helford by road on the 6th of june and can lend you one, if your desperate PM me and I can post it and pick it up then

 

[oldsaltoz]

Try turning it on with no other noise and get down close to the thru/in hull unit, listen for a regular ticking, indicating the signal is being sent.

No clicking, no good.