Mike,
I don't have this depth finder, but have had these kind of problems on others in the past.
Usually, found the problem was with the transducer not the unit. Most common on a puck style transducer that is mounted to the out side of the trolling motor.
Can be as simple as connection problems. If you haven't tried already: Unplug the transducer and check both connections. If there is any kind of corrosion clean connections. Spray with WD-40 and wipe clean.
Also, try moving the wire around while plugged up at the unit connection and at the wire base going into the transducer (do this out of the water). If you notice the unit reading wild numbers like depth numbers jumping quickly, then most likely there is a wire problem (wire streched inside of the shielding) to the transducer. Don't think you can fix this other than getting a new transducer.
If it is not a puck style, then you might just be getting interferience from something.
Might also go to www.lowrance.comhttp://www.lowrance.com and check there for your problem.
Hope this helps.
Justin Hires
www.USABassin.com
National Team Tournament Trail
KY-10 & Regional Director



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