FCV-295 Bottom lock issue



Sorry this is going to be a long one.
I've been running my 295 with SS264N (200khz only) for several years now, it really is a great unit for detecting the hard limestone bottom that we get good fish on.
Typical fishing depths are between 20 and 120m, but I've never had problem getting good readings out to 300m, and pretty much anywhere at any speed, with a slightly broken signal in choppy conditions.

The problem started when I removed the sounder and transducer from my previous boat and fitted to my new one. The hulls are almost identical, same brand, same width, same deadrise, but a metre and a half longer and now with twin outboards, but now I'm starting to lose faith in the sounder/transducer.

The new boat actually had twin Raymarine e95's, a CP450 chirp unit and a TM-265LM transducer factory fitted. I gave them a go, and despite reasonable performance, the lack of bottom lock/bottom discrimination was a big thumbs down from me. So I removed one e95, and fitted my existing gear. I left the tranny, and chirp unit in place for backup - some of our trips involve trailering the boat 1500 kilometres away into the remote North West of Australia, where support (and in fact towns) are minimal to non-existant.

So the first trial after the fitting of the Furuno was concerning, as it was a quick drop in the water at a marina on the way up North for a remote trip. The sounder wouldnt show me the bottom in 2m of water unless I maxed out the gain, even so I could barely get the bottom lock to give a solid return.

I played around with the tranny wires to make sure they had good contact, but nothing changed. Despite no other changes, by the time we hit the water a couple of days later it performed flawlessly. As good as it was in the previous boat. I never stop thinking about intermitant electrical faults though...

Subsequently I have had a couple of trips where the bottom lock return gets broken and basically gives no return. What I find strange is that the right hand screen still reads, but nothing on the left, unless I bump the gain right up, whereapon I get broken and gappy B/L and a useless right hand screen.

So my first thought is that I've damaged the transducer cable during the change, maybe a short or a wire broken. I've given it all a good wiggle with no change.

Next, I thought I'd be cunning and hook up the TM-265 transducer to hopefully establish whether it is the tranny or the 295. Not wanting to de-plug the original cable with the proprietary 11 pin Chirp plug (still waiting for someone to prove to me that the Raymarine Chirp is of any value), I bought a 3m extension cable, deplugged and wired in to the 295, thanks to the excellent information on both this and Airmar's websites. Some advise to anyone trying this approach - the extension cable has different coloured wires inside.
I obviously changed the TXDR settings to suit the different transducer.

So I've taken the new setup out for a play, expecting awesome performance, but what I got was good returns on medium frequency 130khz, with way more breaks in B/L than with the SS264, and on low frequency I'm having the same problems that I had with the SS264 - no bottom lock return.

So I don't seem to have proven anything. I hoped I would either see a broken 295 (HF circuit not working) or everything OK meaning that the SS264 or cable are faulty.

One other thing is that I think I've noticed the 295 screen flicker a bit from time to time, but I honestly can't remember if it has done that all along. It certainly doesn't appear to be linked to the bottom lock problem, but I mention it in case that means something to the experts.

I might slip out tomorrow and try to take some underwater footage of both transducers with my gopro, but I just don't believe that this is bubble related. The hull is plate aluminium with no strakes, and no other obstructions.

Can anyone suggest what I should do next? There arent many fishable days around here, I can't afford to waste them.
Also local Furuno support is likely to be prickley, since the 295 and 264 are of US origin.

Do you have any screen shots of the 295 showing the Bottom Lock?

Sorry, I thought I uploaded the photos with my original post. It seems they were too large and I was too ignorant to notice.
IMG_0573 (Copy).jpgfuruno 026 (Copy).jpg
furuno 022 (Copy).jpg
I don't seem to have any actual photos of the SS264 misbehaving, but it is the same as the low frequency pic with the TM265.

Any ideas on how I can get such strong return on the RH screen, but no BL and no depth?

In your second picture you have the LF gain set to 10. Normally with the gain set that high and in that depth of water, the display would be completely reddish/brown. Your third picture is showing the HF side in shallow water with the gain at 3.8. Here the 295 is showing no hint of a second echo. Normally I would expect to see at least two maybe three returns at that gain setting. I hate to ask, but are you 100% sure you don't have the transducers swapped? Also make sure that the transducer wires are connected to pins 1 & 3 on the three pin transducer plugs.

Hi Snips,
I share your concern for the lack red at a gain of 10, that is what I would have expected.
Unfortunately the image is exactly what I experienced upon first test of the SS264 after the re-install. It remedied itself throiugh no input of mine, and then repeated the behavior recently.
I nearly wept when I tested the TM265 and saw the same behaviour with the LF channel. What should have been an easy trouble shoot just got harder.

furuno 036 [640x480].jpg
furuno 005 (Copy).jpg

I could easily have the pairings back to front for LF and MF, I did my best to work it out from the plug diagrams and a quick continuity check with the multimeter, bearing in mind that the cable is the extension cable, not the actual transducer cable. Seeing the different couloured wiring made my day when I chopped the plug...

furuno 035 [640x480].jpg
Sorry, I cut my post off for some reason just as I was about to show the TM265 in situ. I have already dropped it down some at it was useless the way it was. Do you think I would see any benefit from dropping it further? The top of the RHS is already level with the hull.

furuno 033 [640x480].jpg

Fyi, I have the LF set to 45 and HF set to 140.
And if you were wondering, the shield wires are connected back to the 295 chassis and earthed to the boat hull, even though you can't see them in the pic.

Are there any diagnostics that can be perormed on a transducer with a standard multimeter?

Unfortunately I haven't been able to get out for further trials since starting this post - the summer wind is pretty persistant right now, +25knots and 38 degrees C.

There is very little you can do to check a transducer with a voltmeter. If it were installation related you would notice a performance increase/decrease with the speed of the vessel. In the one pictures it looks like you have only the HF Blue & Black wires connected is this correct? If you TVG settings are wrong they can suppress shallow water targets. Have you tried resetting the 295 to the factory's default settings?

Hi Snips,
Yes, I only have the HF SS264 installed.
I did a factory reset while I was setting up the 265, so TVG is as factory default.

Can you clarify if you are using a 265LH or 265LM?

A bit of time has passed and a couple more days on the water.
Sometimes it works, and sometimes it doesn't.
Both HF and LF have the same problem ie two different transducers - big breaks in the bottom lock.
The only clue I have is that the BL screen has a bit of a flicker in the return, so whatever red I have pulses but only in the BL, not any flickering in the RHS.
I hope this means something to you. What else do you reccomend?
The track record on the 295 has been pretty solid, the few that have failed gave no bottom indication at all. In the pictures you have posted the bottom returns are weak. Weak bottom returns will lead to poor Bottom Lock performance. Below is the LF of a B-265 at the dock with "0" gain. Even though I was using a 1100, the 295 should yield similar results. If you can't see multi returns at the dock all I can advise is to double check your transducer settings and all your wiring.



  • B-265LH #1.jpg
    B-265LH #1.jpg
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Gday Snips

Been looking through some old threads looking for answers on my FCV 295 not being able to find bottom. Just to give you a little info i had the starter motor on my outboard sieze up " rusted inside" which i suspect created a dead short which caused me engine tacho to factory reset but after fixing the outboard the next time i had the boat out the sounder would not find bottom. After checking the battery that the sounder runs on i found it was flat so i charged it but still no bottom. I have tried a factory reset still no good. I am trying to get hold of a transducer to try on it to determan if its the FCV 295 or the transducer

My question is if its the head unit as its sound like it could be one of the few you mention above that failed are they repairable and is it cost effective as i would need to send mine back to the USA from Australia as i imported mine and the local furuno dealer near me will not touch it as its an import one.

Thanks Andrew
The FCV-295 has been a great sounder for us and we will take a look at it for you. Just provide contact information with it so we can get back to you with an repair estimate.