Just got a 595c hummingbird sonar/GPS combo last week and it will not read the depths right and will jump to crazy numbers for no reason.  Cant figure it out, bought a new battery, made sure it was off of simulation mode, but I cant figure it out.  I took it to a spot I knew was 5 ft. deep and it would read 15, 17, 9, and then settle at 5 for about two minutes, then back to 19.  I'm getting a bit frustrated so any advice will help,

Thanks,

Deadeye32

i think theres some setting that if set to high will make it go nuts... i might be wrong play with the sensitivity or somethin maybe

It's most likely installed badly.

Turn fishfinder on and touch xdusr it should be pinging.

If it's shoot thru hull it can be air bubbles or not directly in contact with water.

If it's transom mount  it might be out of the water sometimes or angled towards to boat. A strack could be bubbling the water.

Garnet

I have the same problem with my 595c and a friend of mine has a 700 series that he is having the same problem with. :'( :'( :'( I TROLL FOR KOKANEE here in California and depth is very important. I can correct it by turning it off and on, but then I loose my waypoints and track. If I do nothing it eventually corrects itself.

I am going to tryit on auto depth and default and see if it makes a difference. I won't be able to try it until late next week though.