I was wondering is there a way to turn on the backlight tv shows no power led light.Try to jump 5v std to on/off switch the tv did not turn.
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Re: led46c45rq no backlight
Need more information.... maybe you have a short that is holding down secondary supply voltage? Does the standby (power supply) voltage change if you unplug the main board? -
Re: led46c45rq no backlight
The standby is at 5v the power led is not onComment
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Re: led46c45rq no backlight
Can I see the whole board? There must be more than one connectors on that board.
To turn on the backlights you must disconnect the cables between the power supply and the main board first, then use the resistor between the PS_ON and the BL_ON.
Right now I cannot tell if that ON/OFF pin is the PS_ON pin or the Inverter ON/OFF (bl_on) pin.Last edited by budm; 02-03-2015, 09:33 PM.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
Here is picture power supplyAttached FilesComment
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Re: led46c45rq no backlight
OK, you will need 500~1K resistor between 5STBY and the ON/OFF (PS_ON), and another resistor (500~1K) between 5STBY and the BL_ON.
Make sure to remove both connectors because we do want to back feed the force on Voltage back to the main board.
When the power is apply you do not have to hit the power switch because we are forcing the power supply on manually.
Can we also see the whole back side of the TV?Last edited by budm; 02-03-2015, 11:18 PM.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
Here some more picAttached FilesComment
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Re: led46c45rq no backlight
Here pic of the backAttached FilesComment
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Re: led46c45rq no backlight
What is on the left side of the TV in post 8?
The connector with red, black, and grey, where does it go to?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
Those wires go inside the panel to the led lights and the only other thing on left is the power on button control for volume and channel.Comment
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Re: led46c45rq no backlight
That is lots of wires, I wonder if there is LED driver board inside the panel.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
I dont think there is one in there the leds do cover the whole screen they are not just one strip in bottom or the sides.Comment
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Re: led46c45rq no backlight
Do i disconnect the entire connectors or just the pinsComment
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Re: led46c45rq no backlight
"Do i disconnect the entire connectors or just the pins" which connector?
"I dont think there is one in there the leds do cover the whole screen they are not just one strip in bottom or the sides"
There are 10 wires (5 reds, and black, grey , blue, brown, white) to the LEDs which to me does not look right, can you show where the ends of that cable bundle is?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
Here is picture where they goAttached FilesComment
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Re: led46c45rq no backlight
Why is it everytime i try post a pictures it only posts oneComment
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Re: led46c45rq no backlight
Here is another picAttached FilesComment
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Re: led46c45rq no backlight
Here is a picture of the back of the connector says led pos 5 terminal led neg 5 terminalsAttached FilesComment
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Re: led46c45rq no backlight
I did the jump from sb to bl-on and sb to on/off no back light check to voltage at led connector nothing also checked the 12v pin 1 and 2 of con2 nothing it is like power supply is deadComment
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Re: led46c45rq no backlight
I checked the main filter cap has 170 vAttached 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.
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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.
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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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