Garmin EchoMap 93sv Interference

Hi everyone,

I've done some poking around at some of the other posts, but nothing seems to answer my issue, so here is what I have. When the Trolling Motor (TM) is off, the Garmin screen is clean and looks good. But, when the TM is on, I get interference on my screen. Yes, I did connect ferrite bead, but the interference is still there. Another post mentioned grounding the unit, but where do I ground - negative terminal of battery? TM is ran off two independent batteries, and Garmin is powered off another battery. Screen shots below (not sure which will come up first) show when TM is on, and when off - pretty obvious.

Any suggestions are welcome!

Thanks,

Ed

Attachment 385508Attachment 385509

I would suspect a wiring issue, but it is impossible to say from just a pic. Only 11.5V showing at the unit is troublesome to me. I use a 20AH (or 50 AH) lithium with my 93svUHD and PLS, and I never see less than 12.8V. I am also not using a ground wire nor the ferrite, but 93 wiring and power is independent of TM, and well separated from TM wires to avoid crosstalk.

Mine was worse than that, I have a Minn Kota trolling motor I ground the trolling motor housing back to my battery and still no help I ended up with a half inch block of foam rubber between my transducer and trolling motor an changed my gain and this helped considerably.

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Interference can encroach in 2 possible distinct paths - xducer/xducer cable or the power circuit ...

One should first determine which of these 2 distinct encroachment paths the interference is getting in ...

This is best determined by removing the xducer and the xducer cable entirely from the trolling motor and hang it in the water far away from the TM ...

*If the interference goes away = the interference is encroaching into the xducer or the xducer cable ...
*If the interference is still present = the interference is encroaching into the power circuit somewhere ...

It is less effective to apply interference remedies for one possible encroachment path if the interference is encroaching thru the other path ...

Determine the encroachment path and then remedies aligned toward that specific encroachment path can be suggested ...

Rickie

Nice!! I will do that at lunch today! Thanks everyone - more to come!

Wiring for each too close or neat coils. Maybe sharing a charger and backfeeding.
Just throwing that out there

Rickie - did what you said, and yes, the interference is being picked up by the Xducer. Saw the earlier post where someone put a piece of rubber between the Xducer and motor. Is that the only thing I should try next, or is there other possible solutions?

Quote:

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Originally Posted by KokomoTerror

Rickie - did what you said, and yes, the interference is being picked up by the Xducer. Saw the earlier post where someone put a piece of rubber between the Xducer and motor. Is that the only thing I should try next, or is there other possible solutions?

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*Inspect the xducer housing, the rubber strain relief grommet where the cable enters the xducer housing, and the xducer cable for nicks that can compromise the integrity of the interference shielding capability ...

*Make sure the xducer cable is routed along the TM mounting and away from the TM power wire harness ...

*HB can supply ferrite core rings to install on the xducer cable to sometimes “arrest” interference before it reaches the head unit (HB is 1-800-633-1468) ...

Rickie

I tested it at lunch, and I put the wire against the motor, but did not get any interference. The only time I got the interference is when the xducer was against the motor. I will surely double check all the wires, and look into some ferrite rings. Really appreciate the information!

an old post i know, but i am having the same EXACT issue. installed my 93sv last summer/fall. only get interference when tm is running. can reduce gain to about 50 to eliminate the interference. did you come up with a definite cause/fix?