I have a 597ci hd when boat gets up to 13 mph the depth reading goes crazy could go fom 7ft to 900 and you have to reeboot to get it to work again tranducer is mounted the way it said but it looks like it just about comes out of water its mounted on the transom the way they said thank you for any help.

SOURCE: Brand new 190C. Will absoulutely not display

Like everything made there is always one that just doesn't work. All you can do is check and double check the connections and cables and make sure it is all tight and in the correct connector. I do know that if the voltage is not steady and between 10-13 volt your going to get bad readings. Humminbird has a very liberal return and exchange on transduceers and by contacting them with the issue I am sure they will excange this for you. All you have to do is send yours in and they will replace it. I have done this several times with them and am completely satisifed with their service. You might want to take some mild soapy water and clean the head of the unit, sometimes they can get a waxy type build up and this collect air bubbles and this will also throw it off. I know you probably already checked but is the head firmly mounted and not moving around on you? I have this same unit mounted to my trolling motor and I love it and have had no issues so i wish you luck.
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