lorance elite 4 hdi help

Greeting all,
Hoping some one(s) could help explain and correct what's not happening on my ff. 
Lorance elite 4 hdi (latest update completed)
So..  old unit on the used yak I recently purchased.
"Every thing works great"
I've put in now 3 times twice with a new battery in the ocean same problem as described below.
My issue is that at the 20' mark.  I lose the bottom reading.  Or if its not lost, it is a faint dotted line that is nearly invisible.  I'm on a shallow fresh water lake for the next few days and changed the settings, i and am hoping to get this figured out before leaving.  I've got photos of all the settings and can only think that I've got the transducer wrong on my settings? Maybe..... but even then I should be able to read below 20'if it works at all right?  It's to consistant in losing bottom at 20' to be random I think. I've pulled some numbers off the transducer but am not sure if I'm getting a good cross # online.
Anyone have any suggestions? Help this is super frustrating.  Of course I resented the unit back to factory settings originally to "figure it out".   

Thanks,
J. Ice

OK simple question.
What would make my fish finder stop showing/ reading the bottom contours at 20 ft?
J. Ice

Can you post a photo ?

OK simple question.
What would make my fish finder stop showing/ reading the bottom contours at 20 ft?
J. Ice

Is it set for auto lower range? Does it still display the digits of the depth correctly? Have you tried choosing a manual lower range that is deeper than the water you’re in?

Will do/ try. It's all very frustrating but I have time here at the cabin yo really dig.  Here are some photos from today. Tomorrow ull pull the numbers off the transducer tag and take a pic. Maybe someone can cross the number for a positive ID. If not resolved by Monday um gonna find reception on the water and call tek support.
Any one hanging around Arnold this week?here are a few pics .

Sorry for the rotation.
Setting is on auto and I check frequently cause it seems to change probably me. 
I have not tried the manual setting and and setting it for a deeper range than at.  It does continually show the correct / changing depth 20+' but the contours stop showing. The pic at 19' shows the reading just starting to stop recording.

As you go over deeper water the depth scale on the right should change to bigger numbers to keep up with the depth. Have you noticed if the numbers increase?

They do and depth reading is true as compared to a buddy in SantaCruz. The issue is I lose the conture / picture of the bottom. As if the view is stuck at a programmed depth. But it's not and some times the contour is shown as faint dots. With no definition. I've switched pages with little differance.  I'll report more as I continue to play.

I would use different manual lower range settings so the bottom is displayed on the middle of the screen to see if it is a problem with the bottom of the display. Also try changing the color line to see if that changes how the bottom is displayed.

 
  How is the transducer installed?  Is it over the side directly in the water? In hull install?  if in hull, what is the hull made of? 
  Sonar pulses and air don't mix.  Sound won't pass through air bubbles or air pockets.
If transducer is "Glued In" there may be air bubbles under it causing signal degradation.
My $.02 worth....
 

Thanks all, I will try all suggestions today. The transducer is glued to the hull. Jackson coda 12.5 previous owner stated it was a factory install and all worked previously.  I'm going to try and verify the transducer m# and do a hard reset. Then go thu and try and systematically go thru each setting and see what I can narrow down.  We'll see.  The frequency options are the most puzzling to me.  Especially not knowing for sure which transducer I have.  There are two frequency options.  One for the down scan feature and one for the sonar.  I've been playing with those and think I got the best combination but not sure and will try again today.
Thanks again.
J. Ice

I turn on OVERLAY DATA, set color to green and put the unit in night mode.  That really shows the bottom structure as well as reduce all those rainbow colors.  My set-up; the water is black, the bottom is shades of green and fish are arch green.  Adjust sensitivity so the black water has green flecks in it, then back off just enough to make the flecks go away. 
The high contrast between the black and the green is great in bright daylight too.
This also saves a bunch on battery power.  My FF will run about 4 hours on one amp of battery.  A 10 Ah battery will last me 3 or 4 days of fishing.

While viewing the bottom, press the + key.  This will zoom in on the bottom and make details more clear.  If in auto mode, a screen will pop up asking if you want to get out of bottom mode.  Once you've zoomed in our out on the bottom, press the up/down arrow on the center joy pad.  Keep holding and the whole range of the the display will move up and down.  It will give you an affirmation beep tone while performing this as well as a limit beep tone once you've reached the range limit up or down. 

Make sure your transducer is in good contact.  Just about the worst way to attach a transducer is by gluing it to the inside of your hull.  NOTHING sticks to the hull.  It will eventually form an air gap and kill the signal.  I use a water bath thru-the-hull method where I attached a tuperware container with it's bottom cut out to the inside of the hull.  Yes, it leaks.  But at least I know it's not in contact when the water leaks out.  I have to top off the tuperware well once every day or two.  Sensitivity is excellent this way and the transducer is at no risk of damage.   

Thanks for all the replys.  I got out this morning did restore to factory settings, went thru all the prompts and checked thesettings.
Looks like things are working really good definition st 35'+ but no fish.... that was me.  I like the idea about the color contrasts and bottom lock I will play with that as well.  I think I might have been trying and changing things too much to quickly and might have scrambled the computer.  Thus needing the default restore to clean it all up.
 I do really appreciate all the help and suggestions.  frustrations some time need to be vented and other ideas heard.
Thanks again.
J. Ice

Also, there are some good youtube vids on how to use and set up this particular model.  I particularly like using the first screen option to see where I've been.  Marking fish too.  I've gotten down several channels in lakes that put me right on top of macks and kokes.