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Just recently my 998 si di has started to loose its depth signal at blast off. Depth reads 1.9 ft or 2.2 ft and will stay at that reading for sometime and then randomly read the correct depth few minutes later. Never did this in the first few years of owning the unit (2013). transducer seem level with the hull. Just seeing if someone can put in the right direction to see what is up with the unit.Thanks Chris
Im no hummingbird guy but i fought this issue with my lowerance unit. I tried numerous things. Mine ended up being the transducer.
Redngoo wrote:Im no hummingbird guy but i fought this issue with my lowerance unit. I tried numerous things. Mine ended up being the transducer.ok thanks Redngoo will price a new one I was thinking it may be that.
My vote would be transducer as well. My 958c DI transducer slowly failed over a couple of months, and DI completely quit eventually. I decided to cut it open to at least understand what went wrong. Previous owner had used the stock transom-mount transducer with the TM adapter. Humminbird recommends against this. Turns out too many rock/stump strikes slowly pulled on the wire where it comes out of the transducer, and eventually broke one off inside. No way to re-solder with anything I have at home, much less re-filling with that solidified goo humminbird uses inside the thing.Only problem is the DI transducers are impossible to find. I called all over. Got the “national backorder” story. Called humminbird, got the same. They said they were expecting some the middle of October from their supplier (no doubt in China).
oldtimer57 wrote:My vote would be transducer as well. My 958c DI transducer slowly failed over a couple of months, and DI completely quit eventually. I decided to cut it open to at least understand what went wrong. Previous owner had used the stock transom-mount transducer with the TM adapter. Humminbird recommends against this. Turns out too many rock/stump strikes slowly pulled on the wire where it comes out of the transducer, and eventually broke one off inside. No way to re-solder with anything I have at home, much less re-filling with that solidified goo humminbird uses inside the thing.Only problem is the DI transducers are impossible to find. I called all over. Got the “national backorder” story. Called humminbird, got the same. They said they were expecting some the middle of October from their supplier (no doubt in China).Oh boy….just did a quick online search looking at 300 to 400 bucks Canadian. the one that is giving me trouble is the transom mount may just run to fail and make a decsision to replace at a later date. Was hoping for a easy cheap fix. Thanks oldtimer 57..
I recently ordered a DI transducer for my 1158 from factoryoutletstore.com. No problems and reasonable prices. They also have transducers for the 998. https://fishfinders.factoryoutletstore. … ucers.html
When I contacted them they said “on backorder”. I tried every source I could think of. Then resorted to Humminbird direct (these things are pricey if you pay retail) and they too said “on backorder, expecting some in the middle of October…”The transom mount can take some abuse since it gets exposed to a lot of high pressure water which will flex the cable where it enters the transducer body. The TM mount for the transom transducer is really a flimsy deal and when it breaks, all that holds the transducer on is the cable itself, which is NOT very strong.
I believe that Chris is actually talking about losing 2d, in which case, for HB, that is coming from his glassed in ducer in the bilge area. They are known to fail after a few years. Putting in a new one is not expensive at all, but, requires some work in moving some plumbing in the bilge area, knocking out the old ducer, glassing in the new one, and fishing some wire to the dash.Testing is actually available to confirm failure of the glassed in 2d ducer. It requires being on the water, and accessing the y cable and the back of the head unit at the dash. Firstly, disconnect both ducers from the y cable. Then plug the suspect 2d bilge ducer directly into the back of the head unit. Configure the unit to read 2d from the dual beam 200/83 ducer. Idle around. Readings will likely be erratic like previously.Then, disconnect that ducer, and then plug in the imaging ducer into the back of the head unit. Configure the unit to read 2d from the imaging transducer. ldle around. 2d should work perfectly. If your testing follows as above, then you are confirming failure of the 2d bilge transducer.There are two other scenarios, but not nearly as frequent.If when you test each transducer separately as above, and they both work, then, in effect, you are bypassing the y cable, indicating a faulty y cable.If, when you test each transducer separately as above, and neither one works, then it is likely a head unit problem.But, most of the time, it will be failure of the glassed in 2d transducer. Hope this helps.
catdude28 wrote:I believe that Chris is actually talking about losing 2d, in which case, for HB, that is coming from his glassed in ducer in the bilge area. They are known to fail after a few years. Putting in a new one is not expensive at all, but, requires some work in moving some plumbing in the bilge area, knocking out the old ducer, glassing in the new one, and fishing some wire to the dash.Testing is actually available to confirm failure of the glassed in 2d ducer. It requires being on the water, and accessing the y cable and the back of the head unit at the dash. Firstly, disconnect both ducers from the y cable. Then plug the suspect 2d bilge ducer directly into the back of the head unit. Configure the unit to read 2d from the dual beam 200/83 ducer. Idle around. Readings will likely be erratic like previously.Then, disconnect that ducer, and then plug in the imaging ducer into the back of the head unit. Configure the unit to read 2d from the imaging transducer. ldle around. 2d should work perfectly. If your testing follows as above, then you are confirming failure of the 2d bilge transducer.There are two other scenarios, but not nearly as frequent.If when you test each transducer separately as above, and they both work, then, in effect, you are bypassing the y cable, indicating a faulty y cable.If, when you test each transducer separately as above, and neither one works, then it is likely a head unit problem.But, most of the time, it will be failure of the glassed in 2d transducer. Hope this helps.Correct on the testing procedures. This should be pinned where others can get the detail.John
BCB Might have the transducer in stock and if you call and ask for Michael specifically he can assist you as customer service. We will say that most of these on Humminbird are back in operation after a transducer install, and eventually its becomes the unit on the next failure.
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