I�ve tried everything and talk to Humminbird support. Turning trolling motor and it make my image unreadable. 2D, down and side. Even tried just using the universal transducer and it distorted the 2D. Sonar is wired to my starting battery. Tried grounding it to trolling motor skeg and to boat nothing is working. Anyone having this issue and a fix please share your fix.

Do you have the out-of-balance prop issue that many have due to a defective prop?

I'm assuming you're talking about the trolling motor interference. First disconnect the ground wire you have going to the skeg. Not needed on an Ultrex, it is already internally grounded. Now, look at your batteries and make sure you're not "sharing a ground" between the trolling motor batteries and the cranking battery. This can be in the form of a jump start unit, a defective battery charger, or simply a ground connection made from the cranking to the trolling battery. If you are, disconnect it also. Now, take the top off the Ultrex and check the fuse on the brown wire. If it is blown, replace it. you may still have interference on SI and DI, but it should clear up the Sonar. Next step would be chokes and filters. Humminbird would be the one to lead you into these areas.
John

Thank you for the reply. I have a 1199 unit at the console and it works perfect even when I�m running the trolling motor. It�s my bow unit 998si that�s affected.

Thank you for the reply. I have a 1199 unit at the console and it works perfect even when I�m running the trolling motor. It�s my bow unit 998si that�s affected.

Do you have it wired directly to your battery (and not one of the trolling motor batteries) or did you tie it into an existing wire at the bow? It should have it's own independent set of wires directly to the battery. The next simplest test would be to move it further away to the side of the TM and see if that helps. It did for me. On another unit I went to Radio shack and bought chokes and added them to the wire close to the unit. I did radio shack because it was cheap. HB does offer a couple of different items to add, one goes on the trolling motor wire and one goes on the HB wire. Their tech support should be able to walk you thru steps. You might also want to do a youtube search as there are videos on how to track it down and get rid of as well as search the forum as this has come up several times in the last few years.

Yes front unit has its own wire from unit all the way back to starting battery. I actually moved the wire away from my trolling motor wiring about the last 4 feet. It didn�t help. Humminbird sent me a ferrite ring which I put on the transducer cable wrapped it 5 times then figure 8 and folded over the rest of the excess cable. Didn�t help at all. I removed transducer and connected my unit to the universal transducer thinking at least I can have 2D. Kicked the trolling motor on and it completely wiped out the screen. I had the Terrova before I went to the Ulterex and never had this issue. Very frustrating

Joe, I have an Ultrex with a Garmin on the bow and have zero issues. Before the Garmin I had a Lowrance, no issue with it either. I'm using power from the bow existing hot wire. I would do this if I were you, call David at Shut Up and Fish in Lewisville and explain your problem. I'm betting he can fix it over the phone, he's that good. 972-822-9285

Can you explain what you mean moved the cable away the last four feet. If at all possible the trolling motor cables should never come in contact with the fish finder cables. Sometime it's not possible but every effort should be taken.

If you have an onboard charger disconnect the leads going to the cranking battery

I have center console so the trolling motor wires and my hot wire run up the middle to front deck. I moved the trolling motor wires over to the left side and left hot wire for sonar on the right. They all came up through the front storage compartment so that left about4 feet to trolling motor plug in. Ideally one should be on the left the other on the right but that not possible here. It�s a Blazer Bay 2170

Thank you Aggies. I can try that I guess but the only hot wire up front is for the trolling motor. I was always told to have a dedicated hot wire for the sonar unit.

It�s possible I guess. While working on this issue in my driveway I�d lower my trolling motor down and I�d activate the motor to see what was happening on my sonar. I did notice a the lower unit shaking on speed1-4 but not on 5-10.

One thing I can tell ya from experience is before you decide one solution does not work put the boat in the water. The water adds a grounding element can can't really be duplicated out of water. The unit can show rfi out of water but when you put the boat in the water it is gone.

I would also recommend that next time you are on the water would be to run a temporary power lead from the helix to the battery and lay it on the deck to see if the rfi still exists

Didn't know yours was center console Joe. Still recommend you call David, he can ask you questions about your problem and save you a lot of back and forth on here. I'm willing to bet it's something very simple, usually is. He's a good guy to know if and when you have electrical problems and he's always willing to help.

Thank you 44,I appreciate you help.