Sony KDL 52w5500 No image, no Backlights

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

I'm going to try to check the voltage coming out from de Power supply board

@budm: did you by any change got some time to check a bit further the pictures ?

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

Ok I've been testing the voltage that is comming out of the power supply board, and every thing seems to be OK
Any suggestion on what to test next ?

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

Sorry, been busy, I will download the pictures and give you some test points.

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

Cool

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

OK, on the balancer board (left), what do you DC voltage do you get at CN11 LD pin and the Ground pin, it should be around 11VDC or more.

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

I'm getting 10,85 for the LD pin
and 0 for the Ground pin

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

That is good.

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

Any idea about a next step ?
So basically this measure would mean that the balancer get all the power needed ?
So maybe it could come from the logic board ?

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

I need to download the service manual on your post 20. Something still does not make sense that you do not get any error code. You can try disconnecting that cable, the one with LD, to see if you will get any error code.

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

I do get error code, but I got 2
13 blink
and
14 blink

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

That is correct. Sorry about the error codes question, I got your post mixed up with another SONY post that shows no error codes, sorry about that.
I also forget to ask you if you do have 12VDC at both ends of SMD fuse on the T-CON board.
I did more research and found out that your power supply board P/N 1-487-340-11 is aslo used in KDL-52S5100, KDL-52V5100, KDL-55V5100. I will look to see if the service manuals/training manuals will be closer to what you have.
Power supply board P/N 1-487-340-11: http://www.shopjimmy.com/sony-1-487-...-g5n-board.htm

Master Inverter P/N A-1663-196B: http://www.shopjimmy.com/sony-a-1663...-d5n-board.htm

Slave Inverter P/N A-1663-200A: http://www.shopjimmy.com/catalogsear...?q=A-1663-200A

LCD panel model: LTY520HE12 (same as used in KDL-52V5100)

T-CON LJ94-02638L: http://www.shopjimmy.com/samsung-lj9...-con-board.htm

KDL-52V5100 service manual: http://elektrotanya.com/?q=showresul...oria=&kat2=all

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

I looked through the KDL-52V5100 Service and training manuals, it does have info on the 13x, 14x codes, it only has up to 8x code, even though it uses the same boards as your but the main board is not the same.
So I have to do more searching.
I wonder if you are getting the BL_ON signal, and also the 12V to the T-CON or not.

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

I did check for the T-CON, and it was getting the 12v
as for the BL_ON (I'm guession Backlights ON) is there any way to simulate the signal ? I'm don't imagine that it's as simple as connecting 2 pin like for starting a computer ?

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

We need to find out if the inverter circuit is getting the BL_ON signal or if it is locked out. If it does not have the BL_ON then that will explain why you did not see the backlights flash on before going into protection mode.

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

hum I tried to look around how to do a test on the BL_ON signal, but I did not found any instruction.
Would you have any instruction to lead me on how to test this signal ?

Sorry about all this, I really try to find out most of it myself but yeah sometime that's not enough :s

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

Inverter board D5N connector CN6702 pin 3 (BACKLIGHTS), look for DC Voltage when TV is turned on, Black probe on the chassis, Red probe on the pin.
Also make sure you do have 395VDC on the two pins (measure right at the two pins) of connector CN6600.

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

Oh ok, that was simple enough (I was searching for a BL_ON on the balancer ...)
So I did not see any signal going through (I did the test on both side => CN6702 (inverter) and power supplly board (CN6201)

But I'm a bit suprise to see this, I though that it was the logic board that is supposed to send the signal to the inverter. Why is this wired to the power supply board ? (well this is a curiosity question, don't bother answering, I'll check this ^^)

And I do have 397 VDC on CN6600

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

Hum one more thing, I'm not sure of how strong the signal must be (I've been reading about 5VDC)
But I did re do the test with a bit more precision with my multimeter (2V)
And when it's off, I'm reading 0,001 and when it's on it go to 0,002 VDC
I guess it's not relevant, but I'm no expert so I prefer saying it ...

[budm]

Re: Sony KDL 52w5500 No image, no Backlights

"But I'm a bit surprise to see this, I though that it was the logic board that is supposed to send the signal to the inverter. Why is this wired to the power supply board ?" it uses the power supply board as the junction point for distributing the signal from the main board for clean wiring.
>3VDC = BACKLIGHTS ON
<1VDC = BACKLIGHTS OFF

[goulloux]

Re: Sony KDL 52w5500 No image, no Backlights

Oh ok thx
So now would it make sens to check if the signal is coming out of the main board ?
It look a bit more complicated, the mainboard is not as detail as the inverter, did not found any reference to the backlight