Topic: Loosing depth reading on 798ci hd si

[skeeter2013]

Hello and thanks for the forum. I have a problem and wanted some thoughts on troubleshooting it. Back around April of this year I purchased a new 798ci hd si and installed it with two transducers using the Y splitter cable. The si transducer is mounted in the back and the other transducer for high speed reading is mounted inside the hull. It has been working fine except for some reason it would every now and then stop reading depth and then start back reading depth and this happened just about every time I went out. It will happen when I'm running at full speed and it also happens when idling but will start reading again on its on. It does this in si and hd, does not seem to matter which transducer is being used at the time.

I purchased another 798ci hd si last week so I could have one up front and one in the console and have them connected with the Ethernet cable. I decided to put the new unit where the old unit was and place the older unit up front. With the Y cable connected to the new unit it is still loosing depth reading and seems to be loosing it worse than the older unit. I'm thinking that maybe I have a bad Y cable and it is causing the problem. Has anyone else had this problem?

Also I was thinking that having the two units connected with the Ethernet cable I could runoff the same transducers and external antenna I have installed but that does not seem to be the case. I tried hooking up the one I moved to the front "old unit" with just power and Ethernet cable connected to the new unit but it would only run simulator mode and on screen said no transducer installed. I installed a transducer to it and it is working, will I need to hook up another external antenna for this unit since it does not seem to pick up signal as well as unit with external antenna or is there a y cable for hooking up two units using the same antenna??

Thanks for the help!!

[skeeter2013]

Well just a note to say I figured out the Ethernet problem, found the pdf file online from Humminbird Ethernet and was able to do all the things I wanted to do. Now I just need to fix the problem of the unit loosing depth readings. My guess would be the Y connector but if someone else knows of something else to try, please let me know, thanks.

[rnvinc]

Disconnect the AS SIDB Y cable and plug the in hull Dual Beam xducer directly into the unit ...

This will tell you if the AS SIDB Y cable is bad or if the in hull xducer is bad (or the in hull xducer's installation)...

If the depth problem still exists with just the in hull Dual Beam xducer connected, add enough water to the bilge to cover the xducer ... If the depth issue goes away, the in hull Xducer bonding to the hull has failed and needs to be re-installed ...

Rickie

[skeeter2013]

Thanks for the info, I will try the water test if I have the problem again. I went out Friday to do a test and everything went well on the test. First I set both my units to factory defaults and then put the latest software version to each unit. Then I set up my console unit the way I wanted it and then adjusted the front unit to same settings. I made some runs down the lake with no problem so we will see how it goes on the next fishing trip.

[skeeter2013]

Ok went out today and zero problems with new unit in drivers console. Both units are running off the same transducers and connected with Ethernet cable. The bow unit did loose depth a couple of time but would start reading again after a few minutes while I was on the trolling motor. I checked my console unit and it was reading correctly. There is evidently a problem then with the older unit loosing depth and must be in the unit since both are connected together running off same transducers but only the bow unit is now loosing bottom reading.

[rnvinc]

Are you saying the bow unit does not have a xducer connected to it ... But only gets sonar data from the transom xducer thru the ethernet ... ??

Rickie

[skeeter2013]

I have a transducer hooked up to the front bow unit but I'm not using it. I can go into the menu and choose which transducers I want to run and I'm currently running both units off the same two transducers that I have connected to my console unit via Y cable. When I pull my trolling motor up to run to a different area my front bow unit still shows the same depths when running down the lake as my console unit. I know now that my console unit is working perfectly with no problems but my bow unit does loose depth from time to time when my console unit does not. So I have a problem with the front bow unit that I will probably need to send in for repair since it is still under warranty.

[rnvinc]

It sounds like the Ethernet cable may not be functioning correctly to allow the front unit to see the rear xducer ...

Can you feasibly temporary the bow unit at the console... hooked directly to the transom SI and AS SIDB Y cable setup ... ??

This may determine if it's the bow unit or the Ethernet cable ...

Rickie