Samsung PS64E8005GUXXE - sound but complete black screen

[CoZeNGTX]

hello finaly i might find a good site who can help me solve my TV problem

like the subject says

a TV with sound but completly black screen in dark room no backlight appears to blink or what so ever

so yes tv shud have power if sounds comes out from it

but where shud i start looking for failures? where to messure with multimeters? i can take pictures of the components of the TV backside if needed to help me correct me what parts is what

first of all i cant see any blown fuses or blown caps on those what u calling there is a green light on a small board that i guess it is the T-con board? it blinks withing 4 secs when the tv is on, does that indicate theres is a problem with a component? or is it operating normaly with that speed? readed on other forums it shud blink once every second not once within 4 to 5 sec


sorry for my bad spelling im in need of all help i can get to fix it becouse its a good tv in my opinion

grettings from Tim in Sweden

[downunder]

G'day Tim,

Can you check the Vs voltage at the connector CN5002 between the Y-main board (big board on the left) and the power supply (board in the centre) as you turn the TV on. It normally sits at 211V in a functional TV. If it rises to 200+ V but then drops to 10V, unclip that white flexicable at the bottom right of the Y-main (CN5003).

Turn the TV on again and see if Vs comes on and stays on. You may note that the LED on the Digital board (that you call T-Con) will return to 1 flash per second. This scenario indicates that the Y-main may be faulty.

So, inspect the Y-main and see if it's got 3 small blue 10uf (106) ceramic capacitors near the small transformer roughly in the centre of the board.
These are marked C5050, C5151 and C5153. These should be replaced even if they check OK. This will likely restore your TV to operation.

These are not normal capacitors - they are a high pulse type - and you must use the same kind. Available from RS Components. Also, as the Y-main is a multi-layered board, it's recommended you snip the capacitor leads at the top of the board, and solder new ones directly to the exposed solder pads.

See how you go with that lot - Bruce

[CoZeNGTX]

hello i checked the powersupply for the VA - 55 and VS- 217 as long the y-main board is disconnected but soon as i connect it the numbers dissapears get no reading on thee y-main board either from the pads named vscan or vsch when the y-mainboard is connected but now the t-con blinks every second when the y-main board is disconnected from power and white flexicable

and when i only removed the white flexicable from the y-main that tv started clicking noice

hope this info will help me for further info

[downunder]

So, no Vs unless Y-main is disconnected. X-main volts are derived from Y-main via a wire harness that runs above the power supply. So leave Y-main attached to power supply and disconnect X-main. Does Vs still disappear when you power the TV on? If yes, Y-main is faulty. If no, X-main is faulty.

An ohms check from the Vs pin to a ground pin on either X or y may reveal a short circuit on the faulty board. If so, most likely you have shorted FETs/IGBTs on that board. Check the devices mounted on the heatsinks for shorts. - Bruce.

[CoZeNGTX]

hello again i disconnected the wireharness that goes from y-main to x-main (13 pin cable connector) still no Vs shows up untill i disconnect to the y-main from the power supply so my guess is faulty y-main? by the way i dont see these 3 small blue 10uf (106) ceramic capacitors near the small transformer roughly in the centre of the board that u talked about i can post picture or is the best way now to replace the whole y-main board or is it easyer to repair it?


could not see any short by testing with an ohms check on the Vs pin on both boards

Tim

[downunder]

Yes, Tim, definitely a faulty Y-main. This is not always accompanied by a short from Vs to ground. Other faults can trigger protection which goes via the flat cable from the Y-main to the digital board.

Re the caps, they may not be on your model - see pages 15 & 16 of the attached Samsung news letter for their location. Repairing the Y-main is possible if you can see anything that's burnt out or if any of the FETs measure shorted, otherwise a replacement may be the best option - Bruce

[CoZeNGTX]

thank you for ur help bruce i will try repair this badboy or els i will try find a working one on ebay but there is diffrent one becouse there is alot of them that have big green capacitors thay have 7 of em and mine have 6

my card have these numbers

Model no: 58" / 63" DS YM (2L)
PCB no: LJ41-09453A
REV no: R1.5 (10/12/08)

and white little sticker have ( KB 789B A1 280 00W - BA1 )


PBA no: LJ92-01780A/B/C/D (58DS)
PBA no: LJ92-01789A/B/C/D (63DS)

cant find any good replacement on ebay if im not able to repair this

and btw i think i found these 3 ones but thay are in numbers C5067, C5069, C5068 on the card posting pics

grettings from Tim

[CoZeNGTX]

some1 help me find a replacement part on ebay? would be nice to have this tv working again but there is so much models of this board so dunno witch one to take

[downunder]

Search for the number on the white sticker, LJ92-01789A for the 64 inch model.

Bruce

[CoZeNGTX]

does the number on the white sticker need to be exacly the same? becouse i can find alot of the LJ92-01789A with the white sticker starts with the KB 789B and the BA1 on the end

heres is one

http://www.ebay.com/itm/SAMSUNG-PN64E8000-YSUS-BOARD-LJ92-01789-/282621134481?hash=item41cd884691:g:qjwAAOSwYTVZnL63

[downunder]

Looks like that should be the right one (says LJ92-01789A). You can zoom in on the board shown and compare it to yours. Shop Jimmy also has a few boards. Google shopjimmyparts and type the board number in the search panel. Freight from the USA is sure a killer.

[CoZeNGTX]

does he ship to sweden becouse here in sweden we dont tear down working parts from TVs witch have cracked creens or something thay just throw it away so yeah desperate need this board maybe something more if its not the only y-main board is broken, it might be the t-con board to that need to send signal to y-main to turn on, i dont know actualy how that part works hehe

and for some reason i cant get on shopjimmyparts website i get this (Access Denied) You don't have permission to access "http://www.shopjimmy.com/element-890-105-2099-digital-board.htm" on this server.

[downunder]

Yes, they ship to Sweden, according to the ad. I know you can't always believe the "fully tested" part, but sometimes you just have to take the plunge. If you use Paypal, you have some insurance if you are not satisfied with the product. I've ordered parts from the states, mostly as a last desperate resort, and I've haven't be conned yet.

Your Control board (what you call t-con) will be OK because you said the flashing LED goes to normal pattern if SC20 is removed.
I've read that Shopjimmy denies access at times. Maybe applies to certain unsavoury countries.                 Bruce

[CoZeNGTX]

ok thanks i just ordered a new y-main and well see if the TV comes back to picture  so i hope the x-main dosent need to be replaced to or the y-main side boards along the side is broken to so well hope for the best i will send and update how it goes 

[downunder]

LYCKA TILL