Samsung UN40F6400 standby LED blink wont turn ON

[mugunthans]

Its time to get expert help to fix my TV as its almost dead !!!
Its Samsung UN40F6400 and power board BN44-00622D

The problem is - When power up the TV - standby LED blink twice for 5 Times and relay click but not ON and cycle continue...

Based on advise from other thread on this forum and tested the below.

1. Disconnected Main board cable 20Pins (CNM803)
> LED backlight ON for half of the screen and half of screen flicker. Tear down the LCD panel and diffuser, found only top 3 Strip light UP and bottom 4 strips (2x2) flicker. So, removed the top 3 and swapped with bottom 4 LEDs but still top 3 is UP good and bottom same flicker.
Hope the LED strips are found to be good - Please concure.

2. Voltage measurement without Main board and LED panel connection

Power supply @ CNM803
OD On/Off - 3v
B13V - 13v
B5v - 5v
DIM1,2,3,4 - 3V
A5V- 5v
BLU on/off - 5v
Power On/off - 3v
++++++++++++++++++++++++
LED Driver - Legend
Ch 1-60v
Ch 2,34 - 120v

with/without LED
CM851/CNM852 - 46v/67v
CNM853 - 17v/35v
+++++++++++++++++++++++
Booster reading
Measurement without LED panel connection
Ch 1 - 70V (c9106)
Ch 2,3,4 - 150v (c9206/c9306/c9406)
Measurement with LED connection
Ch 1 - 44V (c9106)
Ch 2,3,4 - 85v (c9206/c9306/c9406)

HOT Caps reading (with/without LED)
CP810S - 305v / 396V
CP814S - 305v / 396Vc
+++++++++++++++++++++++
anyone has schematics of BN44-0622D ?

[dskall]

Re: Samsung UN40F6400 standby LED blink wont turn ON

You swapped 3 strips for 4. Did you swap forth strip?

[mugunthans]

Re: Samsung UN40F6400 standby LED blink wont turn ON

You swapped 3 strips for 4. Did you swap forth strip?

Yes, 4/5 - swapped with 1/2 and 6/7 swapped with 1/2 - same effect (1/2/3 constant light UP and rest flicker)- Hope LED strips should have no issue.

[dskall]

Re: Samsung UN40F6400 standby LED blink wont turn ON

Have you checked your connection between your strips and panel connector?

[Hamie]

Re: Samsung UN40F6400 standby LED blink wont turn ON

http://www.ohmsupplies.co.uk/epages/...8&Locale=en_AU

[mugunthans]

[SOLVED] Re: Samsung UN40F6400 standby LED blink wont turn ON

Its time to get expert help to fix my TV as its almost dead !!!
Its Samsung UN40F6400 and power board BN44-00622D

The problem is - When power up the TV - standby LED blink twice for 5 Times and relay click but not ON and cycle continue...

I got some local expert advise..which is to replace SMD resister RS802 (10R0 - 10 Ohms) and Youtube channel also confirmed the same.

https://www.youtube.com/watch?v=nEzBdUTpe24&t=567s

but I could not source SMD...so I replaced it with normal Quarter watt resister...and Its working

Thank you very much for your valuable time and advise.

[budm]

Re: Samsung UN40F6400 standby LED blink wont turn ON

"HOT Caps reading (with/without LED)
CP810S - 305v / 396V
CP814S - 305v / 396Vc"

Something is not making sense since that resistor is for supplying the Voltage to run the PFC IC and your PFC Boosted Voltage is 396VDC as it should be, so I cannot see the relationship between one strip of LED is not working properly and that 10 Ohms resistor in the PFC circuit.
Or you are indicating that with LED connector in place and the one of the LED strip is not on you are getting 305VDc? I would expect that ALL LED strips will be affected wit 305VDC reading on the main filter cap and it also does not make sense to have 305VDC on the main filter cap when your AC line Voltage is 230VAC and the low Voltage shutdown should have kicked in too.
BTW, what is resistance reading of that BAD 10 Ohms resistor?

[mugunthans]

Re: Samsung UN40F6400 standby LED blink wont turn ON

Not all the LED 7 strips failed...
First 3 is working constant full bright.
Next 2 flicker like flash and try to glow slowly and next 2 setup start flicker try to glow full bright and goes off last 4 dtrip...Same cycle repeat.
I have attached the photo in my previous post.
The resistor reading is (80ohms).
In fact i was waiting for your advice from my first post..
Special thanks to you...

[mugunthans]

Re: Samsung UN40F6400 standby LED blink wont turn ON

The resistor reading is (80ohms).

My Apologies...Its 580Ω