Re: RCA RLED4778A No Backlight no Pic No Response
Same tv, same symptoms. 400deg for 10 mins in the oven for the main board and it works again
Same tv, same symptoms. 400deg for 10 mins in the oven for the main board and it works again
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Re: RCA RLED4778A No Backlight no Pic No Response
Same tv, same symptoms. 350deg for 10 mins in the oven for the main board and it works again. How strange is that, does anyone have an explanation for why this works, and how long has this fix lasted? Also is this the only set that this method has worked on?Comment
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Re: RCA RLED4778A No Backlight no Pic No Response
Bga on the mainboard overheats, try rigging up a fan solution to keep it cool, it may last a long time, without the extra cooling of a fan it might only last a day a week or a few months more than likely. I've seen where a second heating after tv quits working again may work but many times the second heating does not work.Last edited by nomoresonys; 04-26-2020, 09:47 AM.Comment
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Re: RCA RLED4778A No Backlight no Pic No Response
I expect it re-flows the solder. The TV I fixed was my brother's, and he gave it to his girlfriend. I've asked him about it at times and as far as I know it's still working, after 5 years.Comment
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Re: RCA RLED4778A No Backlight no Pic No Response
There's no reason to think if the BGA has only failed after 10 years then it should last another 10, if the reflow is done well. If it's not cost effective to reball then I reflow and I haven't had one back yet.Comment
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this tv is throwing me for a loop. do samsung tvs no longer have the backlight self test feature built into the power supply?
i tested the backlight with my LED tester and it lights up both strips. one of them reads 100v and the other reads 63.7v.
unplugged mainboard from power supply but left backlight plugged in, and then plugged psu wall power in. expected to see backlights light up but see nothing.
according to how ive diagnosed in the past, this would almost always be a bad power supply. replacement power supply was cheap like 20$ from ebay. but still i get not even... -
Full model of the TV is 65UJ6300-UA.BUSYLOR. TV was given to me by a relative as non-operational so I'm trying to get it working so I have a nice cheap upgrade for my living room. This is my first TV repair so if it sounds a little like I know what I'm talking about, I don't.
TV turns on and has audio, but backlight doesn't turn on. Getting 230v from LED+ to chassis. Also can't see anything with flashlight test. Another forum suggested I replace the LED strips because that's the most common failure on LG TV's and the flashlight test doesn't always show results.
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Hello all!
This post will mostly just act as documentation for my undertaken troubleshooting steps for this TV. Advice will also be appreciated for things to try next
Picked up the TV in thread title from a retail returns auction, symptoms were as described. I started my troubleshooting attempts by shorting the 19V PSU rail to the 3v rail with my multimeter... Doh. Big spark, dead PSU, TV not turning on anymore. Picked up a new mainboard and PSU locally from someone here in Sydney, wasn't sure if my butterfingers had killed both and was a big drive to pick them... -
hi
i have a samsung lcd tv
it powers on with sound and backlight but no picture
all voltages from PS are good 12v 3.3v and 5v
whats odd is that at the tcon i tested voltage across the fuse on the tcon and i get 0v
i figured main board issue..so i ordered a used main board....when i put replacement main board in i still have same issue
no 12v at the tcon fuse
i disconnect the panel ribbon cables to rule out any panel issues and i still have no 12v at the tcon fuse
the odds of having 2... -
Greetings everyone.
Please I need help with the above monitor.
Below is the summary of what happened and what I have done:
The monitor started by turning off 2 seconds after it was turned on. It displayed with a backlight when it turned on. However, the standby light remains on after it is turned off on its own, I have to press the power button again to turn it on, but it will go back to standby after 2 seconds.
The backlight driver IC is 0b3350cp.
I applied a 370k SMD resistor on the CMP pin which is pin 6, while the other...11-07-2023, 09:12 AM
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