If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience.
Service mode entry, adjust and exit procedure to many popular brand TVs are given. Never forget to exit the service mode, after all adjustments have been done.
NB: Please read and understand well, the instructions to enter the service mode, before you begin. Be very careful. Note how to "EXIT" the service mode; after entering and adjusting data. This is very important.
Search the site by type in the "brand name"
to your device, in the "Search box at the top right of the display window of the Homepage
" to get gathered related posts.