First trip out with my new to me 998c and all was working great up until I got ready to head in. I got back to the console and noticed the SI and DI images weren't there anymore. I could see a faint line but the entire "picture" wasn't there.
I have 2D sonar from the in-hull puck and GPS with my cards work great. For whatever reason the SI and DI images disappeared several hours into the day. They seemed to come back in a weird way when I was at a fast troll speed and the bow was up a little. When I got out of the water nothing looked different with the transducer or the angle at which it had been set. Could the transducer just have gone kaput?
I'm using a Y-cable for the dual transducer and that is under the dash.

Did you put your hand on the transducer to see if the mount tripped?

I did check the transducer and it was still locked down in place. I know I didn't hit anything.

Disconnect the Y cable and plug the SI transducer directly to the display to find out if the Y cable, transducer, or unit is the issue. Do it on the water.

Ok have to wait till next week. Supposed to rain from pretty much tomorrow till Tuesday. I'll go from there.

My 1199 did close to the same thing, I did a factory reset and it fixed it.

Dang it I wish I had seen this before I went fishing this morning and I would have tried to see if it would work. I did try just the SI transducer without the Y-cable and it didn't work. ill see if I can hit the lake Monday and try that before I head up to OK next weekend. I also took a pic and I'll attach it when I get home so hopefully Wayne can chime in and help out.

^^^^^^This. Check to see if you have the latest software update.

Does anyone else have trouble posting pics direct from an iPhone? I would post them right now but I have to go in and download and blah blah blah. I haven't ever been able to directly post from my phone to this forum.

As far as software I don't have a blank SD card handy to update and it was supposed to have been done before I bought it.

iPhones don't take jpg. You have to convert to jpg by taking a screenshot, editing it, and posting it.

The error message says it's not in jpg or png and I thought the iPhone takes it in png?

Second, how do I know if the factory reset or hard boot happened? I had unit off held power button didn't do anything then I held it while unit was on and it didn't seem to do anything. Held for 15-25 seconds each time.

You do have a Humminbird unit????????

When your settings are changed from what you had, the unit has been restored to factory defaults. If you messed with the settings that turned off SI/DI, the Restore Defaults will fix that.

The Restore Defaults setting is in the Setup menu. Has nothing to do with the power button.

Yes it's a Humminbird and I did the restore settings but I've also been led to believe that there is a hard boot that you can do, kind of like a soft reset on an iPhone. Kinda just clears the memory and stuff without screwing anything major up.

This is what the SI and DI are doing. I still need to go and check it out since I reset everything but does this look like it might be solve-able with a reset or does it look more like the 'ducer might have some issue? The 'ducer looked pretty much brand new when I got it.

If you can and hook up with someone with si unit and switch head units and see what happens. If you can't find someone let me know I could help ya out