Sony KDL-46EX500 2 blinks, then 6 blinks

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

The TV has is 7 years old. I checked the capacitors with a Fluke 115 after desoldering them. I also have a small component tester (Multi-function tester T7), that I did not use ... my bad :-(
I also just want to remind that the issue on this TV came after a lightning surge...
The buzzing is a "physical" buzzing coming from the T6801 transformer.
Just to know, before changing all capacitors, can you give an internal impedance value telling the capacitor has dried ?
It will help in the future for other cases ...
And for now, I'll check the capacitors again with the multi-function tester and report.
Thanks again

[dick_barton]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Lightning surges tend to take out semiconductor components, IC's and the like which are easily damaged by high static charge or voltage spikes.

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Lightning surges tend to take out semiconductor components, IC's and the like which are easily damaged by high static charge or voltage spikes.

Yes, that's what I thought...

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

I just tested the 270 microFarad 450V :

238 uF __Vloss=0.7% __ ESR=0.34 Ohm with the T7 tester
243 uF with the Fluke

[dick_barton]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Have you lifted the panel to check if any one of the CCFL tubes are dimmer than the rest?

What is the part number of U1 on the inverter board.

There are a few 0 ohm resistors around it I would check out.

[nomoresonys]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Maybe test all the components on the inverter board, found this, not seeing a lot of them, maybe you can find one locally, might be worth a shot?:

https://www.ebay.com/itm/Sony-KDL-46....c101195.m1851

[nomoresonys]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Another there for less: https://www.ebay.com/itm/Sony-46-KDL....c101195.m1851

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Have you lifted the panel to check if any one of the CCFL tubes are dimmer than the rest?
.

No, being able to reach the tubes seems very difficult for me...

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

what is the part number of u1 on the inverter board.

2903
pfsg

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

There are a few 0 ohm resistors around it I would check out.

If you mean JR1, JR2, JR3, JR4 on the inverter board, they are OK.
I also checked the others ones on this board...

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Maybe test all the components on the inverter board, found this, not seeing a lot of them, maybe you can find one locally, might be worth a shot?:

https://www.ebay.com/itm/Sony-KDL-46....c101195.m1851

I think I tested all components on inverter board... except U1, as I don't really know how to test it.
Thanks very much for your ebay links. But shipping cost to France is too high.

I'll see if I can can find one more locally, and not too expensive, because this tv does not belong to me but to a neighbour, and I would like to minimize the cost... And also, be sure that I can repair it in the end (which is not absolutly obvious ...

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

budm gave the link to his redlined power supply schematic in this post :

https://www.badcaps.net/forum/showth...607#post372607

and wrote :
"OK, this is how the board functions. I can explain in details as needed."

In his redlined power supply schematic, he writes in yellow squares :

LD = 11-12V = OK
and FB 0V = BAD

As my measures are :

LD = 12.10V and 12.09V during buzz
FB = 0,04V AC during buzz

Do you think my measures are OK ?
Thanks

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

I am sorry, I forgot to attach photos in my first post.

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

This photo shows the reality well concerning the very weak intensity of the SONY logo during its very brief appearence (less than 1 second during the transformer buzz).

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Does anybody have any idea where to find the inverter board ssb460 schematics ?

[dick_barton]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Check C6618. If it's faulty then it may be responsible for reducing the drive signal to T6801 giving way to a lower HV1 & HV2 voltage

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Thank you dick_barton

i checked C6618 :

with T7 tester :
C=976 nF __ Vloss=0.1 % __ ESR=0.23 ohm

with Fluke :
C= 980 nF

I really have no luck ... all my tests show good components !
I'd like to test HV1 and HV2, but the tension is of course too high for my testers.

Maybe is it a faulty IC ?
If I could have a schematic with planned tensions ...

[dick_barton]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

I think the IC on the inverter board may be an LM2903. Low-power dual voltage comparator. Check the voltage between pins 4 and 8 to see if it has a supply voltage.

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

Good idea.

But I get 12 V

[chrisl32]

Re: Sony KDL-46EX500 2 blinks, then 6 blinks

I checked the other pins :

1, 2 3 and 4 are connected to ground

8___12V
7___0.08V
6___6.24V
5___0.22V

These values are NOT changing wether T6801 buzzes or not.
Is this normal ?

I'll try to follow the tracks around the LM2903 to see what is going on ...

https://www.badcaps.net/forum/attach...1&d=1617965463
https://www.badcaps.net/forum/attach...1&d=1617965463