Samsung LN40C500F3FXZA Power on issue

[whatusername]

Picked up this 40" Samsung on Cl was told red light is on but TV will not come on he said he was told main board.. I opened it up Caps look Good i plug it in red light is on but will not power on as he stated.Once i unplug the main board the back lights light up and the screen is blue.Plug in main board and it wont power up.. it would seem pretty cut & dry its a main board issue but i know with TV's anything is possible so i ask the input of More knowledgeable Men

here are some pics

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

Any reaction on Power LED from pressing buttons? How does it behave with T-con disconnected?

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

The wierd thing Tom is i do not see any buttons on this TV unless its has a Touch Sensor. but i tried to press on the front where the butons should be and nothing happens i will remove t-con now. BRB

T con unplugged and it is still the same

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

It does have touch buttons, built into frame. Confusing but they are there.

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

ok well tcon is not connected and it is still the same

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

Pretty much confirms main board is at fault. I don't yet know if anyone has been successful at repairing these main boards.

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

I figured as much.. I would love to learn to repair boards VS having to replace them all the time.. It would save so much money. Any tests i can try with only a DVOM?

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

Voltage regulators -- https://www.badcaps.net/forum/showthread.php?t=22231

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

ok i will read through that but Tom i took off the main board and looked it over with a magnifying glass and i saw this... what do u make of it? VT-803

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

Hmm, yeah, that looks bad. Does that component test as open?

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

i will check now... what am i looking for ohm or continuity?

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

Ohm -- report reading.
Continuity just says if value is below a certain figure.

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

ok well on ohm VT803 shows 0.00
D803 which i believe is a diode shows 122 but if i reverse the leads it shows 139

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

Any "BN##-######" number printed on PCB (not on label?)

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

Bn41-01181c

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

Can't find any schematic unfortunately. Trying to find parts list, found one for 40" LED Cxxxx series but unfortunately it is a different main board.

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

yea im also searching

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

ok what exactly are we trying to find out? maybe i can message a seller on ebay and they will tell me the info? i worked once before for me

[tom66]

Re: Samsung LN40C500F3FXZA Power on issue

Description of what those parts are.

[whatusername]

Re: Samsung LN40C500F3FXZA Power on issue

i cannot find anything not even a chassis number lol this is frustrating. i guess i will just have to order another board