Re: led46c45rq no backlight
Well at least you found the switched transistor that supply the Voltage to run the PFC IC.
Well at least you found the switched transistor that supply the Voltage to run the PFC IC.
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Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809 -
Re: led46c45rq no backlight
That is true learned more how pfc circuit works.Comment
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Re: led46c45rq no backlight
I got the power supply put it in and the tv did not turn on was hoping it would but i knew it would not.I jumped the power supply stby to power and stby to blue on.The backlight came on and i dont see any cracks which is good news.I am thing the main board has problems can jump stb to power on to see if my tcon board is bad.here picture of the tv with backlight on onlyAttached FilesComment
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Re: led46c45rq no backlight
So it has more problems beside bad power supply.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Re: led46c45rq no backlight
Yes thinking it is main board i think this have eeprom problems.just need to figure out how to test it out.Comment
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Re: led46c45rq no backlight
Any ideas how to test it outComment
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Re: led46c45rq no backlight
Well i checked to see if the main board is sending the 5v on off signal to power suppy and it is but i am not getting bl-on. I started probing from main board to see if where the signal is at i looked for voltage around resistor on main board and the back light came on.Dont know if it was board warmed up and came on or if probing there had anything to do with it.it was probably just board warming up i shut tv off and backlight did not come on.Attached FilesComment
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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... -
I bought this p2210f dell monitor to fix. Schematic is the same as p2210.
Behaviour is that monitors comes on but then backlight switches off almost instantly. If I look with flashlight I can still find the "No signal message". So definitely a backlight issue. Trying to advance the issue I proved that the protection circuit is switching off the backlight by shorting out C3 and resistor to disable the INL chip then re enable by removing the short.
This is where it gets interesting. When I disassembled the monitor to solder leads on c3 capacitor I noticed the backlight flickered... -
Hello all,
Am trying to figure out this backlight issue with this A1990 Macbook Pro.
Tests performed:
There is no backlight even with a good screen.
Backlight IC is receiving the correct support voltages.
Fuse F8400 ok
Current sense resistor R8400 ok
Backlight IC is receiving 3.3V on enable pin.
Backlight IC receiving voltage from PPBUS_G3H, aprox 12.5V.
Backlight IC receiving 5V from PP5V_G3S
Backlight IC BKLT_SCL and BKLT_SDA both measure 0.545V diode mode to ground
I2C_BKLT_SCL and I2C_BKLT_SDA both measure... -
I have a sceptre x405bv TV with bad LED strips. The screen displays dimly over the good LED's, and on disassembling it looks like over half of them are dead tested by multimeter diode test on test points. Plugging it in with the panel disconnected (this TV has a combined power and main board), the backlights immediately receive power when the set is plugged in. When the power button is pressed, it flashes brightly then dims, but additional LED's turn or flicker. When it's turned off again some back lights stay on.
Before I order replacement strips I wanted to ask if it is typical... -
Hello, got an iPad Pro A2378 12.9 5th gen with no backlight. Got another test unit without screen, tested the screen, still no backlight with the test unit.
Figured out the backlight on the screen was bad, ordred a new backlight from mobilesentrix, *carefully replaced it* without damaging the lcd, oh well.
Final result, issue is still there, the screen has no back lights. So i'm back to square one, with 3 hours less and 100$ out, issue still on the screen.
The panel is still ok, i can see the apple in the middle of the screen when it kicks in, just no backlight.
Anyone...
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