Fish Finder (depth-sounder) display problem.

Hi all,
I have a Fish-Finder with a 4"
x 5" approx. LCD screen which has vertical stripes (no image) at
various points across it.I am not very familiar with this technology,
I know it has a (square waves?) drive and dedicated ic's for
display.the housing was gas filled (not anymore).Would these missing
bands be caused by bad contact 'tween the rubber connecting pads on
the screen / pcb interface? shame really as the instrument works fine
other than the display.
Thank you for reading this.

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