KDL-40BX450 Not power

[budm]

Re: KDL-40BX450 Not power

Just disconnect the cable between the power supply and and main board to see if the standby voltage will be present.

[enito]

Re: KDL-40BX450 Not power

I had a 46bx420, totally dead, no power LED or anything. Naturally, I thought this was a power supply issue, but after much frustration, it turned out to be a mainboard issue. replaced the mainboard for about 50 off ebay, I gave it to my Girlfriend, and it is still working today.

Cheers,
Alex

Really? can be a good new, try to buy mainboard, can be the solution...hope!

thx

[enito]

Re: KDL-40BX450 Not power

Just disconnect the cable between the power supply and and main board to see if the standby voltage will be present.

Yesterday i tryed this without main board and i dont get voltages, but.. i tryed with the press of power of tv, no power from control. I can try today with control power cause the power of tv, no reaction.

[budm]

Re: KDL-40BX450 Not power

When you remove the cable between the power supply and the main board, then the main board will not function. The standby power supply is always running when you have power to the power supply board by itself without any other board connected, that is why it is called standby power supply, it is always present and running all the time, right now yours are not running and we have to find out why.

[enito]

Re: KDL-40BX450 Not power

When you remove the cable between the power supply and the main board, then the main board will not function. The standby power supply is always running when you have power to the power supply board by itself without any other board connected, that is why it is called standby power supply, it is always present and running all the time, right now yours are not running and we have to find out why.

Now i understand, ok, today i re check this voltage with power supply and multimeter 3v. disconnect the mainboard, i notify news..thx!

[budm]

Re: KDL-40BX450 Not power

You should read this thread:
https://www.badcaps.net/forum/showthread.php?t=25810

[enito]

Re: KDL-40BX450 Not power

Thx for the link for read, now i checked again 3V standby pin 1, and i dont get any read. Multimeter set DC 20V , and no read.. what can be the next step for check in PSU? thx!

[budm]

Re: KDL-40BX450 Not power

Check the DC Voltage right at the two legs of the main cap C6530.
Check fusible resistor R6301 (10 Ohms?)
Check D6201

[enito]

Re: KDL-40BX450 Not power

Check the DC Voltage right at the two legs of the main cap C6530.
Check fusible resistor R6301 (10 Ohms?)
Check D6201

Oki,

Fusible resistor 10ohms i get correct
D6201 i get one read from one direction like diodes, but the other side i get upper read and down to 1 (is like charge and discharge). This diode is blue, no white black diode.
Now DC check in cap6530 how i measure this? need to up the board, no dangerous? cause need to take points under the board. Sorry for ask but wanna take all security

Thx!

[budm]

Re: KDL-40BX450 Not power

Yes it is dangerous so I hope you know what you are doing and know about electrical safety.
You will be working on the power supply board by itself with just the power (220VAC) applied to the board, You will have the bottom side of the board facing you so you can check the DC Voltage right at the two pin of the cap, this is very dangerous since you will be probing the primary deadly side of the circuit so you must be real careful not to touch anything with your hand, you should have the board on the card board.
By the way, you did check the fuses on the board to make sure they are OK, I assumed?

[enito]

Re: KDL-40BX450 Not power

Hi, ok i didnt apply power, but i measured with capmeter the capacitor and is good. Now i see some tutorial about make a bridge of pin 1 (on off) and pin standby for see if backlight start, like samsung psu. What do you think?
https://www.youtube.com/watch?v=n54IurMvr6o

greets

edit: forget my idea, if forget about dont get 3v :/ can make it this test, wtihout 3v standby working