i have been trying for months and just succeeded in getting one of these Zenith monitors going.
first there was low Vs voltage caused by a bad F6668B IC on the upper power board ... i used a F6668M that i obtained as a Panasonic replacement since it was used as a part upgrade and recommended.
there was still just a lit but blank screen that flittered a little...after much trying i found bad solder on the board feeding the power to the screen on the right or above the sub-power switch and leds ... there are three banks of three power semis ... they did not look bad at all .... heat them good and flow a bunch of solder in ... resolder all the power component's terminals ... there is alot of heat generated here....
it works fine now .... i actually added a fan to push air in below this board ... and I also Suggest that You run it in Power Saving mode ... accessable in the menu ... it hardly dims the screen and gives the circuits a break ... noticeably less heat
i thought i'd post this for the archive
john petillo