Rca LED50B45RQ no picture, sound, backlight.

[mustk1ll20]

Bought this tv new 6 months ago. A month ago the screen went black and nothing responded. Unplugged it from the wall for a minute then plugged it back in and all was good.

Yesterday the screen faded white a little bit then went black. Tried unplugging and plugging in with no joy to be had.

Pulled the back off to check for bad capacitors or burn marks and didn't find anything. From what I have read there should be 3 decent size boards in this tv. Power supply, main board, t-con board. I only have 2, power and main. There is 2 thin pcb boards running the length of the tv along the bottom.

When plugged in there is a red standby light. When I hit the power button the lower right side of the tv starts to illuminate then fades to black. Hitting the power button again does nothing after this and have to unplug to get the standby light.

Not sure where to start with this. I found the psu and main board on eBay for $30 each. But don't want to replace both if there's no need.

[budm]

Re: Rca LED50B45RQ no picture, sound, backlight.

https://www.badcaps.net/forum/showthread.php?t=39740

[mustk1ll20]

Re: Rca LED50B45RQ no picture, sound, backlight.

I've taken the tv completely apart. Those are the only boards in this tv. Couldn't find any bad capacitors.

[tvtimmy]

Re: Rca LED50B45RQ no picture, sound, backlight.

I have the same tv with the same problem. Did you ever come up with the fix for it?

[MBAJACE]

Re: Rca LED50B45RQ no picture, sound, backlight.

I'm having the same problems red light when it's plugged in and then blue light stays on screen stays dark can't see menu images anywhere inside . back lights to come on and no cats seem to be to blame . I've taken off the t con board which I've read needs replacing but what could really be wrong with it ? its not eprom, and I have done some reflowing to the memory and main processor chip and get results seeming im getting closer. i used to get blue light for a few seconds now it stays on. I will post results from next flow. so many people fixing these mainboards and i think its reflow/reball type fixes. Anybody here can elaborate? I've been able to power the TV on and off which I didn't use to be able to I used to only be able to Power It Up and the blue light would stay on until I would unplug the TV set I'm also tracking down the firmware which I plan on loading up tonight it had a TV sitting on my table for way too long . I went back to the Reflow again because I accidentally knocked it off it's cooling rack after the first Reflow and figure I better start over from scratch to see if I found the fix

[Nick's Tvs]

Re: Rca LED50B45RQ no picture, sound, backlight.

MBAJACE

You sound like you definitely have a bad main especially if you can only turn you set on but not off. Not sure exactly what you did reflow, but it is surprising that a reflow got the tv to respond to turn off command. These main boards don't run very hot and almost never have cold solder joints.
What test have you done to rule out the EEPROM? It does not sound like an eeprom issue to me but just curious to know what test you have done to rule it out.

I assume that you both checked all of your voltages coming out of your power supply boards, and that you get 12 volts on booth sides of the fuse down on that buffer board

[Shane711]

Re: Rca LED50B45RQ no picture, sound, backlight.

I have this TV. Bad main board. There is a SMD that is burnt. I believe it to be a transistor but I can't be sure. It is marked wyg31 and I can not find this number anywhere online. Can anyone help me to identify it or tell what I can put in place of it? It has 3 legs and here is a picture.

[dick_barton]

Re: Rca LED50B45RQ no picture, sound, backlight.

Hello Shane,
Is the set definitely 50B45RQ and not 50LB45RQ

[Shane711]

Re: Rca LED50B45RQ no picture, sound, backlight.

It is a 50B45RQ. That is what the label says. This guy took it to a TV repair shop and they lost screws and left a mess inside so I am not sure if this is the correct main board for the TV. I am having my doubts.

[Shane711]

Re: Rca LED50B45RQ no picture, sound, backlight.

Well I ended up changing the main board and now it seems I have another problem. Only half of the LEDs are working. I tested the power board for the correct voltages and that was not clear, Seems the LEDs voltages should be 55VDC to 60VDC. So far I have found 1 LED to be bad. So I heated the LED off and replaced it with a used one. I tested the LEDs with the screen removed and they are all working. So I put the TV all back together and then watched a movie on it. Works perfect now.