Depth finder shows solid line of fish always

[The Rooster]

I have a Humminbird Piranhamax 4DI that seems to have issues. In sonar mode and with fish ID on it nearly always shows a solid line of fish at 9 feet deep. Just below that I can see a line represented in sonar form and at first I believed this to be the thermocline, but now I wonder. It seems to be like this always, unless I turn off fish ID or flip over to down imaging. Also sometimes it shows other fish at different depths, and sometimes gives a depth for them that is seemingly correct, and other times every fish is said to be at 9' no matter where it is on the screen. Part of that line or not.

Also the fish finder depth flashed back and forth between showing correct depth and showing 2' deep even over 30' of water. One pic shows this starting to happen. I had a better one though where the screen was split into numerous bars showing 2' and 19' deep back and forth.

I wanted to ask if anyone else thinks this is messed up or am I misunderstand something?

Things I've considered:
1. I'm seeing the thermocline and fish or baitfish relating to it.
2. I'm seeing motor cavitation (but it's still there even sitting still).
3. There is a problem with the depth finder or tranducer.

Things I've tried:
1. Unplugging and reconnecting the transducer.
2. Turning the sensitivity down.
3. Turning off fish ID (this clears it and makes it useable but I don't like knowing it might be defective).

[Donald Garner]

I would say contact Humminbird and talk to one of the tech's there.  It sounds like there's an issue with the unit.  Keep us updated on what you find out reference this issue.

I have the Humminbird PiranhaMAX4 mounted on my G3 1548 Alwed Jon Boat and really like it a lot.   

[Princeton_Man]

I agree with Don. However, I've never put any with in that fish ID. I've enabled it on a couple of units that I've had in the past and it was rarely ever right. I don't know if they pick up the minnows, tadpoles, and trash, or if it's just to get the angler's juices flowing. I would always rely on the 2D imaging.

[coldfront]

Things I've considered:
1. I'm seeing the thermocline and fish or baitfish relating to it.

depending on where you are....  it might be a thermocline.  but it seems awful early for those to set up...

if you could get a screen capture image to share it might also help a lot...  whether you're asking HERE or in conversation with HB techs...

[The Rooster]

Things I've considered:
1. I'm seeing the thermocline and fish or baitfish relating to it.

depending on where you are....  it might be a thermocline.  but it seems awful early for those to set up...

if you could get a screen capture image to share it might also help a lot...  whether you're asking HERE or in conversation with HB techs...

I posted several images of the screen showing the line I described. Did they not show up?

[coldfront]

I bounce back and forth between my home PC and more mobile devices while 'on the road'.  just checked this morning (at home finally) and yes, the images are there.

look forward to hearing from your conversations with HB techies...

[The Rooster]

I got in contact with Humminbird. They agree it is most likely the transducer that is the issue. They gave me a part number in case I needed to order it. The problem is that a new transducer costs about 70% of what the entire unit costed me to buy new. Also I just bought this in the summer of 2021 and didn't install it until late fall cause I didn't even have the boat yet when I got it. It worked fine all that fall, but by spring of 2022 it was beginning to do this and has gotten worse since then. At first I didn't think much about it cause it wasn't this bad and I just figured it was me who didn't fully understand what I was seeing on the screen. I barely know how to read one of these things. But now it is obvious something is not right. Given the cost of a repair, it looks I'm gonna be replacing it instead and it'll be a Lowrance next time. I've already picked out a Lowrance Hook 5 Reveal to replace it. I'll add a few more pics of what the Humminbird was doing on the last trip out. If it was just a solid line of fish 9' down I'd just turn off fish ID and live with it but when it jumps back and forth from 20' to 2' then it makes the screen unreadable. Looks like bars on a window.

[Donald Garner]

Tks for the update.  I had an issue with one of my Humminbird PiranhaMAX4 couple years ago.  The cost to fix it was almost as much as I paid for the new replacement.  I just went and bought another one at Walmart back then the price was like $90.00 dollars there about  . 

Good luck with the new electronics. 

[apenland01]

My buddy just picked up a Lowrance Hook 7 from Bass Pro on sale and it has a great image.  It's the tripleshot version, it's very decent for about $300 including the transducer.  Perfect for the pontoon boat...