Re: Small RCA TV white screen
If it was a sot23-3 marked 339, (in picture 5) it was a FDN339AN N-Channel mosfet. How did you find the correct values of the resistors, if they were burnt? What values did you use? They seem to be the mosfet source resistors, and are likely around 1Ω.
If the mosfet was bad, the drive ic301 may also have been damaged.
This is a SMPS, IC301 is the drive ic for Q305 mosfet that drives the transformer T301. I would check for shorted diodes on T301 secondary like D302, D303, D305, D306 etc.
You are likely missing all the voltages created by this smps circuit
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Re: Small RCA TV white screen
Yeah the cable has a brown latch that slides out then you slip the cable in and slide it back in to lock it. The connection should be good. The resistors are the ones in picture 4 right below transistor. The thing is I replaced the top transistor too but maybe it was the wrong one. The markings on the original transistor were 339 d. The transistor I replaced it with is a N channel. Maybe it should be a P channel?Leave a comment:
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Re: Small RCA TV white screen
The plug in picture four looks crooked, make sure it is seated properly. (the flat cable does not just pull out and get pushed back in, the latch must be released) What resistors did you replace that made it turn on, Resistors don't usually burn unless something else is bad.
I guess the redit bot couldn't help 3 months agoLast edited by R_J; 06-29-2022, 03:51 PM.Leave a comment:
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Re: Small RCA TV white screen
and check all the solder joints: https://www.google.com/search?q=bad+...ih=607&dpr=1.5Leave a comment:
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Re: Small RCA TV white screen
Could be a bad capacitor/s the electrolytic caps are usually the ones that go first, can be bad and not be bulging.Leave a comment:
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Re: Small RCA TV white screen
I guess you can start by testing voltages and posting model.Leave a comment:
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Small RCA TV white screen
I am trying to fix a small RCA TV for a friend. It holds sentimental value for his father. Initially it had what looked like some burned out resistors and would not turn on. I changed out the resistors and now it turns on but I only get a white screen. I have no experience fixing TVs but hope someone can point me in the right direction on what to check or how to proceed. Thanks. Attached are some pictures.Attached Files -
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To ask here... I have few devices with white screen problem, actualy nokia 2220 and some fuji? camera, and try to understand what is common problem to cause that issue.
Yes, both devices work everything else probably ok, I mean, I hear intro melody and keypress click sound, DTMF tone, power on off... all ok.
On desk is nokia 2220 slide, and I check all screen connectors and components arround it, measure voltage drop, but all looks ok. I suspect on slide flex cable, but it look ok and white screen is not interupt while flexing board, pushing conectors, and sliding up down. In attachment... -
Hello everybody! Posting this in hopes somebody has some expertise that leads to a clear path of troubleshooting that saves me a lot of time!
My macbook has the flex cable problem, the one that prevents the screen turning on. Ive been dealing with this for the last 3 years. Last year it went dead and I managed to fix it following youtube tutorials. But my fix wasnt the best, the problem returned a month later. This week, it went dead again. I again tried to fix it.
This time the original cable broke too close to the screen, it can't be fixed without tearing the screen... -
Another TV topic!!
I got this sharp TV that when I first plugged it in it showed the sharp logo and then went to the input screen. This was about 30 seconds and then it showed white screen. Now I can't see anything but white screen. This has a separate TCON and Main.
The TCON is getting 12V and several parts are as well but the VGH line is only .5Volts which I thought is totally incorrect.
Am I on the correct assumption that the TCON is bad somehow if I'm only getting that voltage or is there something else I should check?... -
Hello,
I have a Dell G15 ryzen edition (ryzen 5) that turns on but won't post, black screen, keyboard lights on, caps lock led on, fans turns and the battery indicating light is showing 2amber and 1 white according to dell website it's a cpu failure, but i tried few basic things before i open it up i tested the screen by pressing the d button before powering it up but it didn't show anything i tried the ctrl+esc for bios recovery but still black screen i tried refreshing the screen, i plugged it on an external monitor but same thing. Next step i unplugged the battery and kept pressing the... -
Hi all, I’ve got a problem I hope someone can help me fixi.
I have a Panasonic TX-48CX350B tv , it powers up ok but the screen is blank, the backlights are working, there’s nothing else though, no picture or sound. I’m not sure what the fault is called whether it’s BLANK/ BLACK/ or WHITE SCREEN I’ve actually came across this before on a similar tv but just ended up scrapping it, I will upload pictures of the boards etc , if anyone could help me I would really appreciate it...01-11-2025, 03:18 PM
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