Disabled TV does not work
How to fix a TV with a multimeter
the most common problem with sets of that age, is that the main board or the front buttons for whatever reason shifts a bit and they do not line up internally to each other which would result in the buttons not always work or the remote may not always work. The usual fix is to release the main board from its holders and slide it back away from the front of the tv, then re-seat it back into it's proper spot. The buttons should now be re-aligned along with the remote sensor. Check it for proper operation if you can, before re-attaching the back cover!