Samsung PN43E450A1F - STONE DEAD

[eychin]

picked this up at e-waste site so no background info. tried turning it on with the button on the lower left and with remote but nothing, not even indicator light. opened the back and tested the fuse and it was fine. check the voltages and the were either zero or very low, i.e., 0.005. no visible signs of damage on the powerboard - all the caps look fine. can i assume it is only a defective powerboard?

[eychin]

Re: Samsung PN43E450A1F - STONE DEAD

i was mistaken or the electricity just back on.
the voltages on the connection to the mainboard are:

PS-ON 2.35
STBY 5.28
GND 0
D15V 0
GND 0
GND 0
D5.3V 0.02
D5.3V 0.02
GND 0
D15V 0
D15V 0
D5.3V 0

the voltages to the buffer board? that is connected to the left side:

1. GND 0
2. PS-ON 0
3. VS_CON 0
4. VS-ON 0
5. GND 0
6. D5.3V 0
7. D15V 0
8. GND 0
9. VA 0
10. NC 0
11. VS 0.06
12. VS 0.06

as mentioned before, there are no visible signs of defective components.

[Andrew F. Ali]

Re: Samsung PN43E450A1F - STONE DEAD

Are you hearing the relay/s clicking when you press the Power button?

[klubbammer]

Re: Samsung PN43E450A1F - STONE DEAD

Hi. I had an identical fault on the same model tv and it was the rectifier that was faulty.Worth checking on your one. Regards

[eychin]

Re: Samsung PN43E450A1F - STONE DEAD

andrew, it has no sound at all.

klubbammer, where is the rectifier you mentioned>?

thanks to all.

[R_J]

Re: Samsung PN43E450A1F - STONE DEAD

Disconnect the plug on the Y-sus board and check the resistance between VS and ground on the Y-sus and also on the X-sus boards
Shopjimmy has a X/Y board repair kit, I would check the fets etc. for shorts.

[Andrew F. Ali]

Re: Samsung PN43E450A1F - STONE DEAD

Disconnect all connectors from the PSU, leaving the ac 120v in connector alone in place. Put two 120Vac household incandescent light bulbs in series and connect it across the Vs and GND pins on the connector that would have gone to the Y-sus Bd. Jump the VS-ON to the STDBY pins. Jump the PS-ON to GND. connect the 120Vac. If the PSU is good the light bulbs should light up bright and constant. Measure Va, D15 and D5.3, they should be spot on.

[eychin]

Re: Samsung PN43E450A1F - STONE DEAD

RJ and Andrew Ali,

i will try your suggestions. please check back on wednesday. thanks.

[tom66]

Re: Samsung PN43E450A1F - STONE DEAD

Once you do Andrew's test, unplug TV power, wait 30 seconds, remove bulbs, connect Y-main and X-main to Vs/Va connector, disconnect LVDS cable between main & control boards, then jumper pins 3-4 on control board (see below) and you should see test patterns. If you do, main board is bad (NOT the same as the control board, main has HDMI etc), so replace that.

https://www.badcaps.net/forum/showthread.php?t=26790

[Andrew F. Ali]

Re: Samsung PN43E450A1F - STONE DEAD

+1k

[eychin]

Re: Samsung PN43E450A1F - STONE DEAD

sorry for the 1 day delay. RJ, the resistance was 1 or in other words, the circuit was open for both the connections you asked for. however, when i first touched the pins, the ohm meter jumped around but then settled down to 1. it did that initially, and then the other time it just was 1.

Andrew, i was confused with your instructions. you asked to remove all the connections to the PSU, the one connecting to the X-sus and the other connecting to the mainboard (w/ HDMI ports). then you asked me to connect the 2 light bulbs in series to the connector that would have gone to the Y-sus board. did you mean the connector to the X/Y board as there is no connection from the Y-sus board to the PSU. also there is no direct connection from the PSU to the X/Y board, but there is a connection from the X-sus board to the X/Y board. lastly, how will the light bulbs get power if all the connectors to the PSU are disconnected?

You also asked me to jump the VS-ON to the STDBY pins. these two pins are located on two different connections on the PSU, the VS-ON on the connector linked to the X-sus board and the other on the connector to the mainboard. are these the two pins u want me to jump?

as for the 2nd jump, the PS-ON to the GND, does it matter which connector to use?

Thanks to both of you for your time and patience. these newer samsung TVs are a lot harder to fix than the ones that simply had bad caps.

[R_J]

Re: Samsung PN43E450A1F - STONE DEAD

1 (one) ohm is a short. That is NOT an open circuit. most meters will show OL if it is open.

[eychin]

Re: Samsung PN43E450A1F - STONE DEAD

i have a cheapie meter. when it is set to ohms, and the leads are touching, it is zero. when they are not touching the number 1 is in the middle of the screen.


also i mislabel the boards. what i refer to as the x/y board is called the x main board. sorry for the confusion.

[eychin]

Re: Samsung PN43E450A1F - STONE DEAD

sorry, my wife distracted me, it is the Y main board located to the left when looking from behind and is connected (side by side ) to that long rectangular Y-sus board. thank you for your patience.

[Andrew F. Ali]

Re: Samsung PN43E450A1F - STONE DEAD

No. It's the Y-Main Bd that connects to the UPPER Y-Buffer Bd and LOWER Y-Buffer Bd. Could we see photos of the back of your TV so we could see how the Bds are interconnected. You are calling the Bds by incorrect names so you are not only confusing yourself but without photos to see what you are talking about and trying tp give long distance assistance is confusing to me, also. Remember we don't have the TV in front of us.