Yes I have been reading all of their stuff on the bbc! Good info on that page for sure! Thank you

Make sure you test with boat in the water. You may have interference while boat is on the trailer but be gone when you drop it in the water. I spent 2 days battling with this and just got pissed and went fishing. Got it in the water and it was gone. Been that way every since

I have a Fortrex 101 and older Humminbirds front & back. I have the same issues. Seems impossible but the problem is consistently way worse on some lakes than others. On the front 997 with trolling motor on I get consistently minor interference on Fork to consistently heavy interference on Squaw Creek. I guess the salinity of the water affects the amount of interference(best guess I've got). Have heard it's a common problem with the built in transducers but I'm using an add-on external transducer. My fuse under the TM cover is fine(that explanation never makes sense to me but I still wish my fuse had been blown). Very aggravating! Wish I could get mine resolved. Hope you do!

Thanks guys, and I have tested it on the water with the same result interference. I really think it is the old fortrex tm I have on the boat. I am just going to order a new ultrex tm this coming up week!! Got the ok from the wife!! Wahooooo I think this will work I hope lol!

If you are using the US2 on that 101 for your 2D sonar, then quit using it.

I went through this with a 101 a few years back and the only thing that worked was using an external transducer. And we tried every known solution and even tried a few that others had not at the time.

I am using external transducers and have not used the internal one built into the tm.

I am having this same exact issue. It's only when I'm running the TM then some times when I'm not.

Very frustrating to invest over 6k in graphs and have this issue. I've tried everything with no luck. With shield and bracket, without shield and bracket, moving up and down the head. Nothing

Do you have an onboard charger? One thing I just saw was disconnecting your cranking battery (or what battery your graphs are powered with) and trying it and seeing if it gets better. I'll be trying that

Same here Clark, I'm at the point were I dunno what to do! I feel like the TM graph is very important when fishing and I can't get the thing to work right. I'm going to try one more thing, and that is taking off my tm and putting a new one on my boat at the dealership and see if that works before purchasing the fortrex. Will post my findings this coming up week.

Yes I have a mk on board smart 4 bank charger. Another thing I was going to try is grounding the cranking battery to the tm battery.

Have you tried disconnecting the charger from The cranking battery? Interference can bleed through the chargers sometimes

Have you contacted MK?

https://www.humminbird.com/faqDetail.aspx?id=3660

I have an ultrex and get the interference, so getting that won't solve your issue. In fact I get interference when I move the pedal on the ultrex. It has something to do with the DI g2n, bc two guys I've spoken to have the sonar g2n and ultrex with no issue. That's why I thought it was the incorrect transducer causing the interference. I spoke to a guy on BBC and he said Humminbird sent him a new TM ducer at no cost.

I have an ultrex and get the interference, so getting that won't solve your issue. In fact I get interference when I move the pedal on the ultrex. It has something to do with the DI g2n, bc two guys I've spoken to have the sonar g2n and ultrex with no issue. That's why I thought it was the incorrect transducer causing the interference. I spoke to a guy on BBC and he said Humminbird sent him a new TM ducer at no cost.

I'm running a MotorGuide X5i with a Lowrance Hook 7 and would constantaly get interference when I ran the TM. I had the transducer cable zip strapped to the TM power cable from where it plugs into the bow and leads to the TM itself to make the wiring look clean and tidy. After doing so research I found out this is a no no. Separated the wires and the interference went away.