Have this sammy LN40C650L1FXZA, all the readings at power supply connectors appear correct, have ol on the 450v filter caps, with tv plugged in and on or off, checked bridge rectifier, read good in circuit. Not sure what to check, tv will make the power on sound/music, backlight will maybe flash, very brief if at all, when turn tv on get solid red light, when turn it off red light blinks 5 times then goes out, can see no menu with flashlight, no obvious signs of damage to anything, sorry for no pics. my camera crapped out. THANKS for any help.
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Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
Your title and post conflict somewhat. Basically it seems PSU is OK and set is normal until backlights due so I would be checking if they can be forced on. If so mainboard suspect for blon/dim signals or firmware problem. -
Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
I think having no voltage at the 450v filter caps is bad but don't know what the cause is.Comment
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Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
No way you can have 0VDC between the two legs of the main filter cap and still able to have backlights and standby power supply running.
You should have about 160VDC between the two legs of the main filter when TV is plugged in and NOT turned on, do you have that?
Can we at least see the pictures of your power supply board?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: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
No both on and off while plugged in, read ol.Comment
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Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
OL on the DCV scale that means it is higher than the meter can display.
What scale on the meter did you set it to?
You should know how to read your meter by now.
As I indicated, now way you can have 0VDC on the main filter cap, operator error.Last edited by budm; 02-19-2018, 03:24 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: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
What is the power supply board P/N?
BN44- ??????
If I remember correctly, this power supply is know for having low PFC Voltage due to bad feedback resistor network.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: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
Think I got some low readings on a few of the transformers on the inverter board.Last edited by nomoresonys; 02-19-2018, 03:57 PM.Comment
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Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
on 200, I get 15.8 on both caps. my bad have about 170 and 385, ok theyre good.Last edited by nomoresonys; 02-19-2018, 03:47 PM.Comment
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Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
Ok I'm suspecting the inverter board.Comment
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Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
You think maybe I could have one bad cfl, making the tv shut down? Thanks for the help.Last edited by nomoresonys; 02-19-2018, 04:06 PM.Comment
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Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
What voltage is going to inverter and is it constant. I would also check that board screen connection is good just a few taps with a pencil end or some such to see if any flash. More likely what budm says though.Comment
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Re: Samsung LN40C650L1FXZA Backlight flash no voltage on 450 v. filter caps.
Is this your PSU ? There is also a circuit diagram on elektrotanya but comes up in images when board number googled.Attached FilesComment
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This specification for the Samsung Galaxy Book 2 Notebook can be useful for upgrading or repairing a laptop that is not working. As a community we are working through our specifications to add valuable data like the Galaxy Book 2 boardview and Galaxy Book 2 schematic. Our users have donated over 1 million documents which are being added to the site. This page will be updated soon with additional information. Alternatively you can request additional help from our users directly on the relevant badcaps forum. Please note that we offer no warranties that any specification, datasheet, or download...09-07-2024, 05:50 AM
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Hi everyone!
Hope you're all having a great day, and thank you very much for stopping by and taking the time to read this post to help me with my parents' Samsung TV.
My issue: No backlight.
Model: QE82Q70RAT
Type No: QE82Q70RAT
The TV was already serviced by Samsung once under warranty for the exact same issue, but six months after the fix, the backlight went out again. Now, Samsung is asking for nearly the same price as a brand new TV to fix this with the same 6-month guarantee.
So hopefully, I can fix this cheaper.
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Hello Sharp TV experts
Our Sharp LC-80LE642U displays one short one long flash error code which is a backlight error. I went into service mode and there were 8 lamp error counts recorded. I reset the count to 0 and did a reset. The last monitor error cause was 16 B00014639:12. 16 is the code for backlight error. I tried to power the tv up but went back into error mode.
> I checked voltages on the power supply board and they all check out .. including 3.28 volts at the error pin.
> There is power to the cpu and T-CONN and no faults found there. The cpu has a flashing...01-24-2025, 11:51 PM -
TV was fixed just after removing Samsung's rear snap cover.
This curved TV's construction is rather interesting. When the snapped on back is removed, rest of the TV will relax the curvature. Top of LCD panel is loose as it wants to straighten out against the slightly curved bezel. Snapped back provide most of the curvature shape. So just simple disassembly of rear cover will allow the rest of the TV frame to relax its curvature. Thats probably what fixed it but no idea which connection. 4x LEDs are edge lit.
Maybe PSU->backlight connector didn't have a good contact?...07-23-2025, 12:34 AM -
- Prior owner tried a replacement main board. No difference.
- Samsung 2x red blinking standby LED = panel fault
- Jumpered FB_TRDY_1 (pin 1 CN1300 left. main tcon->left side buffer boards) and FB_TRDY_3 (pin 95 CN1301 right. main tcon->right side buffer boards) This allows testing individual T-Con (on main board) connection to panel on this Samsung. Found fault on left side (viewing from rear of TV)
- Each side has 2 buffer boards, disconnected left side flex between 2 buffer boards. Fault is on the left most board.
- Tape masking eventually isolated to CN1300 pin 15 (CKV4_GOA) Display
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