I have a fortex 112 that was just installed. Love it. the problem is that when I activate the foot pedal it puts vertical lines in my humminbird 898 locator. I had a maxxum on there before this and did the same thing. the wierd part is if I flip it around to reverse and back up it does not do it. Called humminbird and they have no answer and say they never heard of that. There answer was to call Minnkota. checked to make sure the transducer was mounted properly.(as shown in minnkotas illustration) anyone ever had this problem? if so what is the fix.
I think it is a wire shielding problem. If your transducer cable runs next to the power cables on your trolling motor, I'd try to separate them. The other option would be to insulate one or the other to minimize the interference.
if shielding is the problem then would it not do the same thing in forward and reverse? I think that if it did it both ways it would be easier to fix. I have the same unit at the wheel so going to swap out and see what happens. Could it be the transducer somehow? I think I am into a process of elimination.
Assuming your unit is hooked up to your cranking battery. Unhook your charger from the cranking battery and see if it is back feeding thru it. If so humminbird makes a choke to hook to your charger. If you call them they will send you a ferrite ring to put your transducer cable thru. It could also be a shielding problem between the transducer and the trolling motor itself.