Help with shadow onboard tuner failure

[Mischief]

Hi my wife’s Ubass onboard tuner stopped working.

The preamp portion still works fine and when I first turn in the tuner the screen lights up b. And the flat Led comes on. The b. then turns off (screen remains blank) and the flat Led remains lit. The Led does not change when it’s in tune or sharp it just remains lit in the flat position.

Any ideas if this is an easy fix or what I can do?

I just bought my wife a new shirt scale bass and we want to sell the Ubass to recoup money or fund an amp. I really would like to fix this first before putting it up for sale. Otherwise it’s mint with new $100 strings and still sounds phenomenal. I’d hate to have to sell it without a working onboard tuner.

Cheers

This is what the tuner looks like.