Samsung 26in LN26B360C5D no picture good sound

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

The fuse is fed by 165VD, so you are seeing 56V at the output side, that makes no sense to me, 56V at the input side of the fuse also?

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

That QP802S is for the PFC Voltage booster circuit which is not working right now since you are only getting 165VDC. If you are truly getting only 56VDC, that is not enough to run the 5V Standby power supply either.

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

whats next?

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

Please recheck the voltage on the fuse again, it cannot have 109Vdc voltage drop on that fuse, that is impossible condition.

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

ok when i pop out the fuse and measure across i get 164vdc

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

That is what you will get when measure between the output of the power supply and the load. Pop the fuse back in and read the voltage drop across that fuse.

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

at what point would you like me to connect me neg on the board to get the right reading? im not to technical on boards testing

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

testing from one side of the fuse to the other i get 0

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

The fuse is sitting in the fuse clips, so just put each probe of the meter on each of the fuse clips with fuse in place, polarity of the probe does not matter. We are measuring the voltage on the fuse body.

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

i get 0

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

That is what it expect which means you cannot have the reading of 56V at the fuse. How do you measure this 56V reading? Did you use the negative leg of the filter cap as your ground point as I have instructed?

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

by filter cap you mean cp815?

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

Yes, the negative leg of CP815, which is what you used to take the reading the voltage of the CP815 that you have reported the reading of 165VDC. What ground point did you use to take the reading of 56vdc?

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

the voltage from the cap is going up and down and that was the most common number i was seeing the lowest was 3 and the highest was 90 some

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

But you told me you are getting 165VDC on the cap earlier. How did you get 165 when you said the highest is 90v/

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

Right now you can get the board on sale for $59 with free shipping.
http://www.shopjimmy.com/samsung-bn4...t-inverter.htm

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

when i took out the fuse thats what it read across the fuse clips

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

I would like to learn more about testing this rather then buy a new board if thats ok with you?

[budm]

Re: Samsung 26in LN26B360C5D no picture good sound

So if you put the fuse back in and then measure the DC voltage on that filter cap direct on its two legs, you are getting solid 165vdc?
By the way, that MOSFET should not be getting hot since the PFC is not working or it is switching on/off at the wrong frequency due to fail PFC Controller IC, if the MOSFET is shorted out, it would have blown the main AC fuse by now. I would suggest you to get the replacement board at this point.

[DakotaH]

Re: Samsung 26in LN26B360C5D no picture good sound

will you please just work with me it still does everything that i explained before all it is doing is powering on with no display but good sound and indicates the changing of channels by the led blinking.