Humminbird 587ci not working correctly

I just bought a used boat with a humminbird 587ci on it. It doesnt seem to be working correctly. It often cuts out and doesnt read the depth or reads it wrong, mainly while the boat is in motion, also, it barely picks up any structure/fish. Just wondering if anyone could give me any ideas on what could be wrong. Thanks

I bought a new ducer and that seemed t be the problem. Thanks for all the help fellas. Now I need to get my hands on a chip for it.

Sounds like a call to HB tech support is in order. In my recent experience with them HB has excellent support. Don't know how old your unit is but maybe covered under warranty. cbreeze

Cbreeze, it does it when I drift also. and I noticed that even anchored the depth jumps from around 9 to less than one periodically. I'm pretty sure my ducer is junk. Im gonna try lowering it once cuz it looks pretty high on the transom, and Im hoping the signal is reflecting off the aluminum somehow. I doubt it will help though.

How fast are you going when you get the bad readings? Does it work OK when you drift? Reason I ask this is because the standard transducers only work up to about 10 mph. Faster than that you need a high speed transducer. Reason I know this is because I just bought a new boat and I called HB posing the same question and was told about the limitations of the standard transducer. They were very helpful and gave me the correct part number for the high speed transducer which I went out and purchased. It is being mounted on my new boat as we speak. Hope this helps. Cbreeze

ok thanks. I'll look into that.

Sounds like the ducer is not mounted in a good spot or it is bad all together. You can download a pdf file off the Humminbird site on how and where to mount the ducer. Plenty of videos on youtube as well.