TV flashes backlight then reboots over and over. no image. Client said it used to have image for a bit before rebooting. Got worse over time.
tcon is built into mainboard.
Only one cable goes to panel boards.
there is a cable from one panel board to the other that links them.
cost cutting measure that results in us having harder time to diagnose.
removing the link to the second panel board allows TV to stay on with stable backlight but no image.
used cut off tape method to mask 1 maybe 2 pins on the side of the cable that goes to that second panel board. maybe pin 11 or 12. that causes TV to come on and remain stable but still no image. TV has some voice feature that talks and says something about setting up the tv.
checking panel boards I see no 12v coming in.
checking on the mainboard I see no 12v on the caps close to the lvds cable or on the coils around there, or on the voltage regulator.
seeming like it must be a main board problem but do I also have a panel problem since I was able to use cut off tape method to gain stability? Why does having the second panel board plugged in make it reboot? if there's no 12v going to the panel boards anyway, why should masking a pin do anything at all to change operation?
there is no 12v but the tiny voltages that carry the picture information are there and I assume the clock lines too. some error there maybe tells the main board to shut down?
This is the newest tv I've been called to work on. Made in 2020. Shame on samsung. I see evidence of the challeges to come for us as they keep cutting costs and making things easier to break and harder to fix. The back of this TV had no screws which might be nice if it wasn't such a pain to separate all the clips. Ends up being more work in the long run. The tcon built into the main, I have never liked, but only one cable to the panel and daisy chaining the panel boards makes it so u can't easily test left and right of the panel by disconnecting a cable. You can only easily test the first board. Oh and the power supply being directly connected to the back lights with no wires is probably another issue that could make diagnosis harder in some cases. Whew!
tcon is built into mainboard.
Only one cable goes to panel boards.
there is a cable from one panel board to the other that links them.
cost cutting measure that results in us having harder time to diagnose.
removing the link to the second panel board allows TV to stay on with stable backlight but no image.
used cut off tape method to mask 1 maybe 2 pins on the side of the cable that goes to that second panel board. maybe pin 11 or 12. that causes TV to come on and remain stable but still no image. TV has some voice feature that talks and says something about setting up the tv.
checking panel boards I see no 12v coming in.
checking on the mainboard I see no 12v on the caps close to the lvds cable or on the coils around there, or on the voltage regulator.
seeming like it must be a main board problem but do I also have a panel problem since I was able to use cut off tape method to gain stability? Why does having the second panel board plugged in make it reboot? if there's no 12v going to the panel boards anyway, why should masking a pin do anything at all to change operation?
there is no 12v but the tiny voltages that carry the picture information are there and I assume the clock lines too. some error there maybe tells the main board to shut down?
This is the newest tv I've been called to work on. Made in 2020. Shame on samsung. I see evidence of the challeges to come for us as they keep cutting costs and making things easier to break and harder to fix. The back of this TV had no screws which might be nice if it wasn't such a pain to separate all the clips. Ends up being more work in the long run. The tcon built into the main, I have never liked, but only one cable to the panel and daisy chaining the panel boards makes it so u can't easily test left and right of the panel by disconnecting a cable. You can only easily test the first board. Oh and the power supply being directly connected to the back lights with no wires is probably another issue that could make diagnosis harder in some cases. Whew!
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