Fish finder individual circuit?

Gents
Does a fish finder need to be on a completely independent circuit?

Fact is I'm grasping at straws a bit. I just got off Garmin tech support and there is nothing they can tell me I have not done.
Still under warranty ☺.
Symptoms are unit barely reading bottom. Not revealing any structure, no arches,. Even max gain will not wash it out.
840xs.
Transducer is ticking away strongly.
Unit hangs up, barely moves , or moves but barely shows bottom and is of no use right now.
I will remount back to transom (on TM now).
Reconnect it to separate battery
Transducer is TM150M

Thanks

Still under warranty. Package it back up send it back. Most of the time they just send you a new one anyway. They don't even want to figure out the problems.:twocents

Did it work correctly when it was on the transom?

Don't know that it will solve your problem, but yes run you a separate circuit for each finder. I run a twisted pair of 12 gauge wires to help reduce chance of interference. These new finders require quite a bit of juice to work right. And they do some crazy stuff with low voltage.

Cray is right about running a twister pair.

Ok
twist red & black from fuse box to finder?
or all the way from battery to finder?

Quote:

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Originally Posted by brettw

Ok
twist red & black from fuse box to finder?
or all the way from battery to finder?

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From battery to finder ... with a blade type fuse in the positive wire at the battery end ...

Every connection added between these 2 points adds more voltage drop across the length of the entire circuit ...

Rickie

I doubt that this is your issue. You are more than likely apt to have a bad unit.

I don't like to use the fuse panel because of what was mentioned above. I do however hook to the wiring block that is under the helm of my boat. The difference is that I personally wired this block direct to the battery (positive and negative side) and know that the wire will support anything I put on it. Sometimes, manufacturers wire their fuse panels with mediocre wire. Plus, you have your gauges, livewell, bilge, nav lights, and everything else potentially drawing power from the panel.

I use a wiring block just the lesson the amount of runs directly to the battery. There is a formula based on the amount of amps and distance from the battery as to the size wire you will use.

That said, send her back, I'd bet it is a faulty unit built on a Friday afternoon by a guy that was ready to hit his own boat and fish!!!

Quote:

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Originally Posted by rnvinc

From battery to finder ... with a blade type fuse in the positive wire at the battery end ...

Every connection added between these 2 points adds more voltage drop across the length of the entire circuit ...

Rickie

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Plus adds to the possibility of picking up interference.

Yes,
last year , it was working well on the transom.
I'm moving it back but I can't figure out how it will help.
I have everything turned off and the transducer is just hanging on the TM when testing.
It's the same as having it on a stick.

One thing I am also going to do is put it on its own separate battery. I got one of those small ones and I ran if off that one last year.

thanks guys,
I'll post results next week when I can get out,

See if Garmin will send u another transducer

Does the unit behave, while in simulator mold? If so, would think, bad transducer

Yes, in sim mode it's perfect
. But I always figured simulation was just a program in the machine and had no determination as to whether the unit was working well or not.
I assumed every FF is amazing in simulation mode.
correct?

Check transducer and follow wiring all the way to unit. Be sure no other units are on or trolling motor that can interfere. Also check settings to be sure sonar is turned on. Sounds like may be bad transducer or interference. I would run the self dedicated power wires and be sure you have plenty of voltage.

Here's a screen shot of what I'm getting,

Attachment 201778

This is is maxed out with gain, never saw a fish, brush, bait or even interference

That just ain't right Brett ...

You should send Garmin those screenshots ...

Rickie

I did offer to send them but of course, they want me to put it back on the transom and try it all over again, that will be a pain in the butt and sort of kill another fishing chance,

Rickie,
I'm going to switch power source back to the solo battery, see what happens, but as far as drilling or finding the sealed holes in my transom, I'm not to keen on.
Your thoughts? Could it make any difference where the ducer is as long as there is not any other electronics running?
I know to try and stay away from the feed wires etc.. but this thing is not doing nothing. Hanging it on a shut down TM is the same as hanging if off one of your Da Ducers, correct?

thanks

For sake of less conflict during discussion with Garmin ...

You might think about temporarily connecting a battery right at the head unit ...

This would give you argument that your boat or its wiring cannot be the cause of the issue ...
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Yes ... An xducer on the foot of the TM with the TM not running should not create interference ...

Rickie

thanks,
that really what I'm doing, i have a separate battery sitting there and it has plenty of power to run my HDS 9 for hours and hours, so it should be good enough. Plus , it works well in the garage.
I just got to go dunk the boat again after work and try it one more time. Loading a boat after work only to check on failing electronics is not much fun.

forgot to mention, the pic is max gain and max color

Quote:

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Originally Posted by brettw

forgot to mention, the pic is max gain and max color

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There should be so much clutter at max gain that you wouldn't be able to tell what color the background is ...

Rickie

indeed,
thanks

next will come the issue of shipping costs,