Samsung UN40D6400 led problem

[Malachi]

Re: Samsung UN40D6400 led problem

okay, i saw the photo,

you have each side had 2 strip separate each one had 3 Group , each Group had 12 Diode

its 7030 6 Volts Diode,

Ok? What does that tell us? Do I need a new psu? Lol

[Malachi]

Re: Samsung UN40D6400 led problem

With my meter in diode mode this, I assume, diode beeps everyone I test it. It's on the board but none of the others beep.

[Diah]

Re: Samsung UN40D6400 led problem

you need LEDs one by one by as Diode measure them, not as power them.

[budm]

Re: Samsung UN40D6400 led problem

Your board is Samsung BN44-00427B (PD46B2_BDY) Power Supply / LED Board?
http://www.shopjimmy.com/samsung-bn4...upply-unit.htm

[Malachi]

Re: Samsung UN40D6400 led problem

Also bbs801 beeps but I don't think it's a diode.
Also another one like it labeled bbp801 beeps.

[Malachi]

Re: Samsung UN40D6400 led problem

Correct budm, it is.

[Malachi]

Re: Samsung UN40D6400 led problem

you need LEDs one by one by as Diode measure them, not as power them.

I'm sorry Diah, I don't really understand what that means.

[Diah]

Re: Samsung UN40D6400 led problem

you saied some Leds on back light not powring up. u need to check them if one Diode shorted then all strip die.

[Malachi]

Re: Samsung UN40D6400 led problem

As the pictures show 3/4 or more of the LEDs work.

[budm]

Re: Samsung UN40D6400 led problem

Check the CH1+, 2+, 3+, and 4+ (Anodes Voltage feeding pins) one at time by leaving the probe on one pin at a time and see how high the Voltage goes up too and then drops down, do that on all 4 + pins, Black probe on the chassis.
The drivers has 4 boost converter circuits to feed 4 stings of LEDs.

Pictures provided by shopjimmy.

[Malachi]

Re: Samsung UN40D6400 led problem

I appreciate the help budm, do I touch those with the red lead and black to ground on the chassis? Can I do it with the led unplugged?

With the led unplugged the all got to about 320v for the high and then to about 240v for the low.
And then it cycled back up.

[budm]

Re: Samsung UN40D6400 led problem

I appreciate the help budm, do I touch those with the red lead and black to ground on the chassis? Can I do it with the led unplugged?

OK, LED connectors in place, Black probe on the chassis, red probe on the CH1+ pin, you to have leave the Red probe on the pin then turn the TV on and look at your meter when TV is turned on and then wait may be 5~10 seconds to see if the Voltage drops down, repeat the same on the other 3.

[Malachi]

Re: Samsung UN40D6400 led problem

Ok. Connector in place ch1 high of about 325v, low of about 225v, ch2, ch3 and ch4 about 116v high and about 90v low.

[Malachi]

Re: Samsung UN40D6400 led problem

Do you mean unplug it to see what it drops down to? Because I don't get 5 to 10 seconds before it turns back on.

[budm]

Re: Samsung UN40D6400 led problem

Ok. Connector in place ch1 high of about 325v, low of about 225v, ch2, ch3 and ch4 about 116v high and about 90v low.

OK, as you leave the red probe on CH1+, you turn the TV ON then you see the Voltage jumps up to 325V and also see the backlights flash on then the backlights go out and the Voltage drops down to 225V, is that correct?

[Malachi]

Re: Samsung UN40D6400 led problem

Correct. Give or take 1 or two volts. It goes so quickly it's hard to see.
Just did it again. I guess the low was about 250v.

[budm]

Re: Samsung UN40D6400 led problem

Correct. Give or take 1 or two volts. It goes so quickly it's hard to see.
Just did it again. I guess the low was about 250v.

And doing the same to the other 3 and they do not show the same result as CH1+, is that correct?

[Malachi]

Re: Samsung UN40D6400 led problem

Correct. 116v high about 90v low.
Do I need a psu?

[budm]

Re: Samsung UN40D6400 led problem

OK now do it without the LED connectors in place.
They should all show high Voltage and really close readings to each other.

[Malachi]

Re: Samsung UN40D6400 led problem

I already did that. Post #31. I did the edit I think as you were typing #32