Good day folks. I thought I'd offer you a possible fix for a Samsung TV with a BN41-00611D power supply which doesn't turn on. If all or most of these symptoms match yours, you could be having the same defect as I did and this fix might work for you as well:
-standby seems to be fine, LED is on and the TV responds to the remote control when attempting a power-on
-when the TV tries to turn on, the LED blinks twice in rapid succession, then pauses for a second and repeats, almost like an error code
-both fuses on the board are OK (obviously, since there is power)
-STANDBY 5v is OK (also obvious since the LED stays on)
-BL ON and PS ON signals are present on their pins
however
-backlight doesn't come on, even with main board disconnected
-PFC is not starting (only 230v on the main cap instead of 400v)
-12v output is too low (reads around 8-9v in my case - may vary, but definitely out of spec)
The PFC section was the first indication of where I should start my searches, since with the PS ON signal present, it should begin to operate and boost the voltage on the main cap up to around 400v, but mine only read roughly 230v, so:
-PFC IC ICP801 on the back of the board only had 9v on its VCC pin (pin 8, easily identifiable by cap CP812 connected to it).
I then followed the trace to see where it gets its VCC from. The actual problem came down to a small 10 ohm SMD resistor (RS802) at the other end of the board, on the side opposite the PFC IC. It took me a while to trace that VCC line all the way back to it, but as soon as I put my probe on the other side of the resistor and got a more normal 15v, I knew I had to check the resistor itself and I was right: instead of the required 10 ohms, I think it gave me like 490 ohms, which was already very far off, but just to be certain I removed the resistor (which is why it's missing in one of the pictures, since I snapped it just after I measured it) and sure enough, nowhere near close the value written on it - it developed a higher than normal resistance for some reason.
Mine had 10r0 written on it, but other boards may have it marked with 100 which is the same thing, 10 ohms, which is actually what the replacement one is marked as (the one you see in the picture) and it worked flawlessly, so don't worry if the numbers/letters are not identical...hell, you could even botch a regular resistor if need be.
Now PFC started up and boosted the voltage on the main cap to 395v and the TV turned on. I was a bit hesitant at first, since low value resistors may sometimes act as fuses, thus a failed resistor may be like a blown fuse and point to something else being faulty further down the line, but since I couldn't read any obvious shorts in major components, including the ICs themselves, I took a deep breath and just went for it. I can imagine it may not work for everybody, of course - you may have a different fault altogether or some of the symptoms may still match despite this resistor being fine, but thankfully our wonderful community is friendly and willing to help
Cheers guys (sorry for the pictures being slightly too dark).
-standby seems to be fine, LED is on and the TV responds to the remote control when attempting a power-on
-when the TV tries to turn on, the LED blinks twice in rapid succession, then pauses for a second and repeats, almost like an error code
-both fuses on the board are OK (obviously, since there is power)
-STANDBY 5v is OK (also obvious since the LED stays on)
-BL ON and PS ON signals are present on their pins
however
-backlight doesn't come on, even with main board disconnected
-PFC is not starting (only 230v on the main cap instead of 400v)
-12v output is too low (reads around 8-9v in my case - may vary, but definitely out of spec)
The PFC section was the first indication of where I should start my searches, since with the PS ON signal present, it should begin to operate and boost the voltage on the main cap up to around 400v, but mine only read roughly 230v, so:
-PFC IC ICP801 on the back of the board only had 9v on its VCC pin (pin 8, easily identifiable by cap CP812 connected to it).
I then followed the trace to see where it gets its VCC from. The actual problem came down to a small 10 ohm SMD resistor (RS802) at the other end of the board, on the side opposite the PFC IC. It took me a while to trace that VCC line all the way back to it, but as soon as I put my probe on the other side of the resistor and got a more normal 15v, I knew I had to check the resistor itself and I was right: instead of the required 10 ohms, I think it gave me like 490 ohms, which was already very far off, but just to be certain I removed the resistor (which is why it's missing in one of the pictures, since I snapped it just after I measured it) and sure enough, nowhere near close the value written on it - it developed a higher than normal resistance for some reason.
Mine had 10r0 written on it, but other boards may have it marked with 100 which is the same thing, 10 ohms, which is actually what the replacement one is marked as (the one you see in the picture) and it worked flawlessly, so don't worry if the numbers/letters are not identical...hell, you could even botch a regular resistor if need be.
Now PFC started up and boosted the voltage on the main cap to 395v and the TV turned on. I was a bit hesitant at first, since low value resistors may sometimes act as fuses, thus a failed resistor may be like a blown fuse and point to something else being faulty further down the line, but since I couldn't read any obvious shorts in major components, including the ICs themselves, I took a deep breath and just went for it. I can imagine it may not work for everybody, of course - you may have a different fault altogether or some of the symptoms may still match despite this resistor being fine, but thankfully our wonderful community is friendly and willing to help
Cheers guys (sorry for the pictures being slightly too dark).
Attached Files
. It is a hotel TV, with a slightly different version of the Tizen operating system than the TVs at home.
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