Re: Acoustic solutions LCD26761HDF no backlight
Heres a pic..thx
http://i1068.photobucket.com/albums/...5/P1000843.jpg
Heres a pic..thx
http://i1068.photobucket.com/albums/...5/P1000843.jpg
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Re: Acoustic solutions LCD26761HDF no backlight
OK, the next step is to find out if the PIN 1 (VDD) of the FAN7711 is getting the voltage feeding it, I have a hard time tracing out where it goes to in the pictures.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: Acoustic solutions LCD26761HDF no backlight
Does this pic help..thx
http://i1068.photobucket.com/albums/...5/P1000846.jpgComment
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Re: Acoustic solutions LCD26761HDF no backlight
I saw that picture but not sure if pin 1 is connected to R976, JUMPER J152 and then goes down some where in the bottom right of the picture, we just need to verify if we do have DC power feeding the VDD PIN1 of the IC or not.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: Acoustic solutions LCD26761HDF no backlight
Black lead to the ground pin4 (GND) of the IC, Red probe to pin 1 (VDD), just do not touch ANY METAL PART OF THE PROBE OR CHASSIS DURING THIS MEASUREMENT IN CASE YOU SLIP SINCE WE ARE WORKING ON THE AC PRIMARY SIDE OF THE CIRCUIT!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: Acoustic solutions LCD26761HDF no backlight
And It is not there when you turn off the power switch? The 15vdc is correct since there is 15V Zener inside the IC.
At this point, it can be the IC is bad since it has the voltage but not sending out the drive signals (PIN 5, 7) to the two Gates of the MOSFET's. One thing I am not sure what those components on the left top corner are for yet. If you do have the 400Vdc feeding the MOSFET's, then I would try new IC.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: Acoustic solutions LCD26761HDF no backlight
Thx for your time & being patient with me..im getting 392vdc measured with fluke..theres this repair kit..do i need it all?
http://www.chsinteractive.co.uk/elec...3-q814-s-c.htm
I cant find the IC830 FAN7711 in my farnells catolouge..thxComment
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Re: Acoustic solutions LCD26761HDF no backlight
eBay: http://www.ebay.co.uk/sch/i.html?_fr...All-CategoriesPlease do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
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Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
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Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
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Re: Acoustic solutions LCD26761HDF no backlight
Hi tom..do these pics help..thx
http://i1068.photobucket.com/albums/...5/P1000867.jpg
http://i1068.photobucket.com/albums/...5/P1000872.jpg
http://i1068.photobucket.com/albums/...5/P1000871.jpg
http://i1068.photobucket.com/albums/...5/P1000873.jpgComment
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Re: Acoustic solutions LCD26761HDF no backlight
Is it the 2 smd resistors 103 & 330 if so they measure Q813-103=10.2 & 330=33.7 in circuit
Q814-103=10.03 & 330=34.0
The big resistor R971-red-red-silver-gold which is 0.22 only measures 00.8 thats in circuit shall i pull 1 leg..thxLast edited by sienoki; 03-06-2012, 08:43 AM.Comment
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Re: Acoustic solutions LCD26761HDF no backlight
Do i need the other items in this kit..thx
http://www.ohmsupplies.co.uk/17PW26-...-Q813/Q814-S/C
R971 1 leg pulled reads 02.4 is this O/C..thxLast edited by sienoki; 03-06-2012, 09:05 AM.Comment
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Re: Acoustic solutions LCD26761HDF no backlight
Probably not the SMDs, R971 is likely the sense resistor. Don't worry about pulling it for now, what does you meter read when the leads are touched?
Also check the two diodes for s/c looks like it's a two-switch forward converter. Big improvement on the old half-bridge Vestel designs which had huge reliability problems.
C878 could also be faulty but unlikely just looks like a snubber.Last edited by tom66; 03-06-2012, 11:19 AM.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
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Re: Acoustic solutions LCD26761HDF no backlight
Tom ive come across this what do you think..the 3 resistors in parallel r817-818-819..ive got 3 new same value from another kit that i didnt need...
When it mensions D861-Q841 & C904 they are print side right alongside the 24vpin out & thatD861 marking AP has readings both ways as i mentioned earlier in this thread..thxLast edited by sienoki; 03-06-2012, 11:36 AM.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... -
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... -
Hi this oldie had no backlight .after replacing caps on 24v rail ,
still no b/l this uses inverter type:1315 B1-16A,
im sure ive come across the same inverter in a samsung possibly le32r88bd ?
all t/x in board test ok ,so i fitted 15k and led to pin 4 of oz964gn ic
this allows protect to be temporary overridden.
b/l now comes on
but the left hand side of pic is gradually darker than the right side
i have the cct for the tv
but it does not have inverter cct.
i opened it up to inspect the ccfl tubes
and they dont have any... -
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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