Toshiba LED TV, blank screen

[MDluffy]

To all:
The TV was working fine, just over a year old. Turn it on one day and the screen is blank. Here are some observations. turn on tv, front small power on green light is on, the red toshiba name comes up and can see fine on a dark gray background. the toshiba goes away, and the screen turns from dark gray to black/blank. Can still hear sound, channels work, input selection works, on/off works, but screen is blank. Changed input to dvd (by guessing at the menu choice since screen bland...), same results. TV model is 46L52000U1. I've disconnected from AC (left for hours), and powered up again, same results. Toshiba forums say this is common, with only answer is to see a repair shop....My question is if someone can point me to a specific module or board that might be bad. I'm very willing to open her up and troubleshoot/replace parts. Thanks in advance. MDluffy

[budm]

Re: Toshiba LED TV, blank screen

Please move this post to TV section, and also upload good clear pictures of the boards.

[MDluffy]

Re: Toshiba LED TV, blank screen

My apologies, I thought I had put in the TV section.
Thank you. Will try to by next weekend. MDluffy

[MDluffy]

Re: Toshiba LED TV, blank screen [46L5200U1]

Here are pictures of the boards. I could not see any obvious vented caps, or other damage. Thank you for any help you can offer. MDluffy

[selldoor]

Re: Toshiba LED TV, blank screen

If when it has gone dark, in a dull room can you shine a flashlight onto the screen from
different angles to see if there is still a faint image.

[MDluffy]

Re: Toshiba LED TV, blank screen

After power up, the big red toshiba letters come up fine, and they are on a light gray background (this has never failed...it always shows the red toshiba). After a few seconds the toshiba goes away, the gray turns to dark black. Used a flashlight and could not see any faint image or grayness at all...

[freakaftr8]

Re: Toshiba LED TV, blank screen

Try heating the tcon board up underneath the metal cover.

[selldoor]

Re: Toshiba LED TV, blank screen

Try unplugging the leads that go from the Main board to the Tcon and see if the
backlight leds stay on.

[MDluffy]

Re: Toshiba LED TV, blank screen

Heating up - used hair dryer to heat up the TCON, I did not remove the metal section as it looks rather tricky to re-assemble, but pointed the dryer down the side. Seemed like good bit of warmth getting in there; No change in symptoms.
Unplugging main board leads - the toshiba logo did not come up, but screen did turn gray for a moment as it has been doing, then to black. reconnected leads and toshiba came up as has been, no change in symptoms.

[tom66]

Re: Toshiba LED TV, blank screen

It sounds like a firmware/software problem to me, which would probably require replacing the main board. However, there's a small chance you can fix the firmware with a USB update. Try downloading the latest update from Toshiba and putting it on a USB stick. Hopefully it has a method like "hold OK button while turning on" to update, rather than having to do it through the menus (which you can't access.)

[MDluffy]

Re: Toshiba LED TV, blank screen

Thanks, will give it a try and report back. MDLuffy

[MDluffy]

Re: Toshiba LED TV, blank screen

Hello, I've googled quite a bit and have had no luck finding FW or SW for this model toshiba, 46L5200U1....any ideas on where to look? Thanks!!

[tom66]

Re: Toshiba LED TV, blank screen

Unfortunately the only place might be Toshiba themselves. They don't always publicly releas the firmware.

[selldoor]

Re: Toshiba LED TV, blank screen

https://web1.toshiba.ca/support/ceg/...?docid=D000050

This was the FIRST item when I googled it?

[MDluffy]

Re: Toshiba LED TV, blank screen

Interesting... I was searching for "46L5200U1" which shows no drivers available, but when I searched "46L5200U" it did show drivers available as you replied. My TV nameplate indicates the U1...I will dig in to see what the difference is, unless someone here knows. Thanks for your patience and assistance. MDluffy

[MDluffy]

Re: Toshiba LED TV, blank screen

My bad... the link clearly shows the U1 model! Will try and report back. Thanks.

[selldoor]

Re: Toshiba LED TV, blank screen

Good - hope it works - when I google things I often just skim past the first few items as whilst I believe they are there because of lots of hits they are often just sites that pick on anything you google then give a list of loads of other places to look and dont actually have any info.

[MDluffy]

Re: Toshiba LED TV, blank screen

Well, followed the instructions, but since the screen is blank, not really sure if I initiated the load...never saw the light on the USB flicker, couldn't tell from any other observations if it loaded or not. When instructions said to use the right and left arrows to select yes to load, I first just hit enter hoping it defaulted to yes, then again with a single right arrow then enter etc... really didn't get anywhere.
So for heck of it, found a control board on ebay. $43usd, free shipping... Figure that the picture circuitry could be working since we are seeing the red toshiba and gray momentarily. Maybe something is telling the screen to go blank, or not telling it to turn on.... Anyway, will install and report back to all. Thanks, MDluffy

[MDluffy]

Re: Toshiba LED TV, blank screen

Got the control board. Only challenge swapping out was the disconnecting and reconnecting of the connectors....Need to take great care and not tug on wires. CN11 the small ribbon cable for touch keypad is tiny! and very difficult...with some assistance, finally got them swapped. No change in symptoms Moving on to TCON replacement, just purchased on ebay $19... Will keep you posted.
MDluffy

[MDluffy]

Re: Toshiba LED TV, blank screen

Finally found more time to experiment... to no avail... current status - same symptoms (after red Toshiba, screen goes from gray to black/blank); changed both main computer board and tcon with no change in symptoms....