Chosen Solution
Hey y’all. I have a Toshiba 55L621U that turns off soon after it is powered on. Most of my research says that this is a power supply issue, but I have seen some people say it could be a mainboard issue. When I turn it on, after it turns off, the red power indicator light usually stays solid for a bit, and sometimes the red led goes out right after the tv turns off. No blinking lights. Do you guys have any suggestions on how to confirm what the issue is? I’m not hugely TV savvy but I’m tech savvy and I’m not worried about ruining this thing, as otherwise it’s going to get scrapped. Thanks in advance!
Hi, It may also be a firmware problem. The logo showing is a good sign as it shows that the basic fundamentals are there i.e. the screen works, the power works, the connection between the mainboard and the screen works and parts of the mainboard work as well. I cannot find a firmware download for your model but if you happen to find it and since you said that you’re going to scrap it if unsuccessful you have nothing to lose by trying to reinstall (or maybe update) the firmware. If you cannot find it either try contacting Toshiba tech support in your location and ask them if it is available. The TV doesn’t stay on long enough for you to verify what firmware version is installed by navigating through the Menus but the update procedure only requires that the firmware is loaded onto a USB stick and the stick inserted into the TV and then with the TV’s Power button being held operated the TV is powered on, the rest is automatic. Hopefully you are able to reinstall the same version software if that is all that is available. Some brands only allow for updating and not reinstalling the same version. Don’t know about Toshiba though.
I (along with many others I’m finding) am having this exact same issue which leads me to believe it is indeed a firmware issue and nothing hardware related (unless these TVs were all designed to fail at the same time!) - I tried flashing the firmware that Toshiba has on their website but it goes to 20% and fails…I’m guessing this is due to the firmware being an old version and the TV not allowing a downgrade - that said has anyone found a firmware that will work? The version I tried is 20170830113420_update_casttv_uhd_01.04.088_fy17_sc_init_clear.prg which is obviously an old (possibly the original) version. Anyone with a working version out there? Thanks much!
I have encountered such a problem once. You need to check whether the firmware version you downloaded to the USB memory stick is correct.
It’s a bad LED or LED strip. The TV is going into a mode that shuts everything off when the LEDs fail. The ones in the TV I salvaged were five years old and were dim or burned out. You can get the parts at a site like ShopJimmy.com for the make and model of the TV. I bought a full replacement set for $60, double sided tape, and shipping, for a total of $75 spent. However, it’s a time consuming process to repair. I spent four hours just getting the TV apart and putting the new strips in, and in the correct order. There are also a lot of screws holding everything together, and holding the strips down to the back of the TV. I’m on the second afternoon of trying to put it all back together. If you decide to tackle this repair, you should also wear nitrile gloves. Fingerprints on the diffusing layers will ruin them. There are at least four, and they can’t get out of order. You also don’t want to bend them. You also run the risk of cracking the LCD screen if you don’t support it properly when removing it. I honestly wouldn’t do this again. But it was a “free” TV, and I figured I’d give it a shot.
the Led back light is bad check this video: https://youtu.be/LaV6aQ8LIpw
I tried everything and when I unhooked everything I unplugged it and came back in about ten days plugged it in and it actually worked again for about three months then one day the screen turned black again.
Has anybody figured this out I have a 65 inch Toshiba fire TV that when I turn it on it comes up as fire TV and then it goes out I don’t want to throw the thing away cuz it’s actually only a couple of years old anybody has a cure please let me know
