Garmin Fishfinder 250

[Dave and Genny]

The aftermarket Garmin Fishfinder 250 installed on our Ranger 2006 21EC isn't working properly. We see no fish, water temp, depth, or bottom. The transducer is thru-hull. It worked when the broker commissioned the boat with us in April 2011. Next time on the water it didn't work initially, but after messing with it for a long time, we had images for a few seconds. Nothing since. I posted a picture in our gallery because I couldn't figure out how to get the image in this post. Click on the Gallery link to the right of this post. I've gone through the manual and checked all the settings. It seems to me the Fishfinder is not communicating with the transducer. Any ideas on what to look for? We're about ready to buy new equipment.

 

[GulfSailor]

The aftermarket Garmin Fishfinder 250 installed on our Ranger 2006 21EC isn't working properly. We see no fish, water temp, depth, or bottom. The transducer is thru-hull. .

Just to be clear, does your 'thru-hull' transducer penetrate the hull and contact the water, or is it mounted on the inside of the hull surface and beams its signal 'through the hull'?

 

[abcandjrc]

I have always found Garmin's tech folks to be excellent, and repairs either free or quite painless. I have always contacted them using the e-mail links on their web site.

I can't be sure whether the 13.1 figure in your photo is voltage or not, it appears to have a degrees symbol after it, but if it is voltage, power appears to be OK. I can't quite sharpen or magnify the photo enough to be sure. One thing I would try, though, is to disconnect and reconnect all wiring, both power and signal. Signal is most likely to be the problem but making sure voltage is correct can't hurt.

Something to consider once you have this problem sorted out. One thing I found on our R21-EC is that the transducer was mounted in the stowage area under the berth, directly under the steering station. It looked like it was in harm's way if things bounced around in a seaway. I epoxied a piece of large-diameter plastic pipe around it to give it more protection.

 

[Dave and Genny]

The transducer is through the hull and touches the water. The 13.1 is Volts. We've unplugged and replugged the connections but it won't hurt to do it again. Never looked "below" to see what is happening on the inside under the floor. Will check that out next time we are with the boat. Thanks for your suggestions. If all else fails, I will contact Garmin.

 

[abcandjrc]

From your last post I am assuming the boat is in the water. Now that the water temp up there is approaching 50 (I went to school in Flint) it is surely warm enough for a Michigander to dive under and see if the transducer may be damaged. (Funny how no matter where you live water is warm enough for swimming on Memorial Day and getting chilly by Labor Day).

With the unit seeing 13.1 volts, voltage sure isn't the problem, and you can almost eliminate the display unit itself if you can work through the menus. That leaves signal or transducer.

A not-very-likely thought. Is it possible the bottom was done this winter and the transducer got painted? Maybe even taped over? Even that shouldn't completely block the signal, but stranger things have happened.

If you do decide to replace the unit I would suggest mounting the transducer inside the hull. The signal will be just fine and there is one fewer failure mode for the boat. To tell the truth, I am surprised the current installation was through the hull. We had a serious engine mount failure in another boat and the engine fell onto a thru-hull transducer. It was actually holding up a fair amount of the weight of a 1200 pound engine and I sweated quite a bit until we got the boat back to a travel lift.