CLICK HERE for the 332C manual if you do not have it.
It has been my experience that if not married properly - the transducer and cable can become breached - and water enters the connection and starts the corrosion process.
Have a good search for the transducer.
If you have a trolling motor installed - look down near the prop -
some even have them built -in! You'll have to trace down the wire when its on the trailer out of the water.
Sometimes a sensitivity adjustment can be made and it will solve the problem.
Many times there will be an object - like glass or metal that will deflect the sonar and make it act up.
If you are getting it only occasionally - i would suspect debris on the bottom - if the range is out consistently - the transducer is at fault. There are many places to mount it - so tracking it down will fall on your shoulders :D
Your 332C can only translate the info it gets from the transducer - so you're on the right track. Locating it, and testing the connection and wires is the next step. If you cannot locate it - you may just opt to purchasing another - and mounting it yourself to save the labor cost of someone else doing it - and you'll be problem-free for quite a while.
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