Sonar question, Quirky Hummingbird 385ci

I have an older Hummingbird 385ci (2010) which works just fine -- unless I'm in 75 fow or deeper when I don't get a depth or bottom reading. I can see my bait dropping down in the water column until it reaches 75' then simply disappears off the screen. The attached screenshot was taken in about 78'

Any ideas as to what's happening and how to fix it?

Do you have your depth set right? Where's your bottom?

Not a humming bird but with my Lawrence I need to change the depths setting depending on the depth. If it's set at 75 then it will only read to that. Currently mine set to 60 and I change to 30 when fishing shallower.

Or turn your sensitivity up. But I don't see
Your bottom

I usually keep the depth set at 100'. The bottom always shows up and I have never had any problem -- providing that I'm in less than 75 fow. The sensitivity setting does not have any adverse effect.

it has happened to me 3 times where the current is strong enough that the bottom and bait will not show at a certain depth say 85 feet.

had to change the depth to 120 to see bottom, but not the bait


not saying this is your issue, but it can happen

Thanks, Longshank. I will try setting the depth to 120' and see if this helps. What I find curious, however, is that this has never happened to my fishing buddies and the issue -- my baits consistently disappearing at 75' -- has occurred on several different bodies of water.

I can see your unit is set to 100’ at the bottom of your screen and you have no bottom.

What I would do is a hard reset on the unit. Put it back to factory setting and then start your fine tuning. I have a Lowrance that at times would do the same thing. The hard reset would usually fix it.

My last guess is you were deeper than you thought and the bottom was over 100’ down. As for seeing your jig all the way to 75’ and then disappearing that is 100% your sensitivity IMO. Turn it up until you see “snow”/interference on the screen then turn it back down a hair. If you still do g see your jig it could be current sending your jig out of the cone.

Your cable may be damaged or have bad connection. I had this issue with my older unit and swapping the transducer worked great.

Other question, are you using an ice transducer? Or boat transducer? Are you getting the transducer deep enough below the bottom of ice? And is it level.

I agree with trying factory reset first of course software can be strange sometimes.

I have had the same issue and agree with the suggestions of Disco and Mykola for fixing/troubleshooting. Once I had to change the transducer after trying a few of these things and that fixed the issue immediately. Level is a possible problem if you are using a skimmer transducer (esp. in deeper water).

ya, I agree with the other guys also. I was just trying to point out an issue that arises from time to time on Simcoe deepwater fishing.


transducers do fail more often than not


hope you figure it out

I don't use birds, but agree with the others...
Try a hard reset - if that doesn't work, maybe try swapping a transducer with a buddy (if they have birds). You will know very quickly if it starts to work. Depending on the age of your unit, Radioworld could likely hook you up with a new one.

I had to replace the transducer on my Lowrance a couple years ago. I guess they often go, just from them bouncing around in your case, or a wire works it's way loose over time.

Have you tried using it in shallow water? Does it produce the same issue?

Try putting the depth to AUTO and see what happens.

If the bottom of the transducer is really scratched up try takin a bit off with really fine grit sandpaper and see if that helps before you buy a new one.

I did the factory reset and changed to auto depth; now to try it out next week!

Thanks again to everyone for the suggestions.