RCA RTU5540-B, flashes once - no backlight

[Noobwithamultimeter]

Found this TV more than a year ago, got it to turn on on my first try and thought wow - what a good score. Played around with it a bit more and discovered a power fault where I would turn it on, it would flash once and the image would be there but no back light. A solution was to try to force powering it on by unplugging it, plugging it back in and when it finally stayed on I would leave it on 24 hours a day on lower backlight setting.

After about 6 months of this I thought I should try fixing it permanently so I watched some youtube videos and someone suggested to look at your transformers for solder working their way up the legs of the transformers. I looked at mine and tried the idea, dropping about 5 fresh drops of solder on the joints that looked funny to me. To my delight the TV turned on INSTANTLY without issue and I was using it normally for the last 5-6 months.

The issue unfortunately re-emerged and I trust it is LED-strip related entirely and the only thing I succeeded in was establishing a better connection which resulted in success in powering on the tv. Now that an LED or two have burned out since, I cannot power on the TV again.

I started this thread as there is only one other topic with this model, I assume people are not yet having problems with them since it is a 2017 model. I don't want to assume anything being the problem, just wanted to put this out there in case anyone had any ideas as to what else it might be.

[neilc6]

Re: RCA RTU5540-B, flashes once - no backlight

RCA TVs that turn on with no backlight or flash of backlights have bad backlights. Backlight level can only be set in the service menu and standard picture mode runs them at 100% causing to burn out around the 2 year mark after the warranty has run out. New strips are impossible to find even from Chinese suppliers. Don't touch them anymore unless they end up in front of my house for free.

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

I was running mine at 45 out of 100. Even that wasn't low enough to save it. What a scam.

[neilc6]

Re: RCA RTU5540-B, flashes once - no backlight

RCA TVs are white label TVs which I believe are manufactured by Skyworth and sold under a number of brands including Westinghouse and Proscan. Skyworth is producing lower end TVs for both LG and Samsung now. They have a similar chassis style as the RCAs, are made in China vs assembled in Mexico and have a bit better build quality than RCAs.

The one feature of RCA TVs is lower price and you get what you pay for. Picture quality is decent since there are only a handful of panel manufacturers. All brands have LED failures. You could pay a lot more a Samsung or Sony and still have backlight issues after 2 years if you put your TV in Dynamic mode.

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

Yeah that panel is ok, I may resort to an experimental repair using all good LED strips from a broken screen 50". I will post pictures if I go that route

[neilc6]

Re: RCA RTU5540-B, flashes once - no backlight

Think I repaired the LEDs in that model and they kept on burning up even with the backlight level turned down. Ended up ordering 2W LED modules and replacing all the LEDs in the bad strip.

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

Wow. What a tedious job. I don't envy that work.

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

Well I unscrewed the back of this TV and let me tell you - this is the easiest back removal I've ever encountered. I placed the set face-down on my table and unscrewed all the screws, simply pulling the back off containing the LED strips in one piece. I didn't even have to handle the delicate LED panel or diffuser sheets once! Whew! Now I'm happy no damage or dirtying will occur to the panel whatsoever.

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

I just tested 12 leds in a row and they are all working. Also I see no burned looking or black ones. Could it be something else preventing the tv from coming on? Like the EEPROM?

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

I'm onto something here, just powered up the TV and saw that ONLY the left side illuminated for a split second, then turned off. It looks like ALL the LEDS are fine! So there is something wrong with the driver for the right hand side for some reason...

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

Switching the power connector from left to right exhibits the same problem, (left side still turns on for a split second) so it appears there is something in the right hand set of LEDs that's preventing them from turning on...

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

So I can confirm that EVERY single LED lights up. I took a video of each side, slowed it down and then watched it for each side of the tv, one connector at a time. The problem it seems is the ability for my power board to deliver enough power to turn on both sides simultaneously. I am confident it needs a new power board, or possible repair (not likely since I'm a noob)

[Noobwithamultimeter]

Re: RCA RTU5540-B, flashes once - no backlight

Whatever was preventing it from turning on, after re-connecting everything it seems to be resolved! The TV is now working! However, I will never turn it off again for fear the power board is on it's last days, and also because LED strips always burn out leds the instant you power them on just like light bulbs, soooo...

[tech9pc]

Re: RCA RTU5540-B, flashes once - no backlight

I have the same one. Same problem for about a year now .... grey screen when turn on sometimes. If I leave it on for about 8 hours straight the next time I turn it on it works fine. If I shut it off in a period of less than 8 hours I have to unplug it 2 or 3 times to get it back up. I know it would not be the power supply, panel or mainboard because it works like a dream when on and is a great 4K tv with excellent picture. So it has to be either the t-con or led strip causing the power on display glitch. I have held off on ripping it apart ... but have not found a solution either.