Chosen Solution
Hi, Judging from the fact I had to create the device page, I am not super optimistic in this being solved, but I bought this TV, And it wouldn’t even turn on. The standby light would come on When plugged into the wall however nothing was displayed on the screen and the backlight would not even turn on. After ordering a repair kit from thetvguy.com and replacing the main board powerboard, backlight driver board, and another smaller auxiliary board (off of the main board) the TV would boot up the backlight would turn on. The Toshiba logo is then displayed for brief moment before the ENTIRE screen (literally nothing at all) turns black with the backlight still on. None of the buttons on the main board are responsive. After some digging I figured that the issue may be the T con board so I bought a replacement and just put it in. Based on the fact that I’m posting here you can probably guess that it made no difference. Any input at all as to what might be causing this issue would be greatly appreciated and I would be more than happy to answer any questions to help get this resolved. -Grant
Hi @grant_mlack , What is the model number of the TV? Toshiba is not helpful as far as service manual go etc as they don’t want you to know. just asking as you didn’t mention it, but did you try different signal inputs or input types e.g. coax, HDMI, Component video and also can you see the TV menu screens at all? I realize that you said that none of the buttons on the mainboard were responsive but I’m not quite sure what you meant. Has the mainboard got buttons or did you mean the TV (or remote control) control buttons then? Since the TV gets to the logo stage, however briefly it appears that the screen is OK and also from the mainboard to the screen as the logo is in the software on the mainboard. Maybe search online for “Toshiba (insert TV model number) firmware” and check if there is any and if it can be manually installed in the TV. I don’t know about Toshiba but with other makes the firmware can be installed via USB without having to go through the menus. Simply plug in the USB with the firmware and turn on the TV. It checks the USB port on startup for a file with the correct filename and if there loads it and installs etc. With some other makes however you need to navigate through the menus to do this so obviously no good in your case if it is the same. Still worth a look anyway. Make sure that you get the correct firmware as installing the wrong firmware can brick the TV. Although since you have replaced the mainboard the firmware should be OK. Again just asking did you verify that the mainboard is compatible with the TV model?
DEAR SIR, Good backlight and “Toshiba” displayed on power up, then unresponsive MEANS YOUR MAIN MOTHER BOARD HAS A PROBLEM 1.YOUR T CON BOARD, PSU BOARD IS OKAY AS TOSHIBA LABEL WAS ON DISPLAY IN STARTUP GET AN USED OR NEW MOTHERBOARD OF model 65L5400U , REPLACE THE PROBLEM ONE AND START IT UP, IF DISPLAY OK THEN THE FIRST THING YOU DO CHECK THE WIFI SETTING, RESET AND DOWNLOAD THE SUITABLE FIRMWARE FOR THAT MODEL……..AFTER THAT YOU GO TO TO RESET FACTORY AND RUN THE PROGRAMTHE SOFTWARE WILL INSTALL ITSELF AND THEN LATER U MUST TRY YOUTUBE APP…..IF IT IS RUN WELL THEN YOUR TV SHOULD BE FINE….
