KDL-52EX703 6 blinks

[holmzy]

I get 6 blinks / flashes on this tv. have managed to switch it on but the backlight is dim when BL_ERR is put on a resistor to ground. Any Ideas please?

[holmzy]

Re: KDL-52EX703 6 blinks

only has 3 boards in view psu, av main and t-con

[R_J]

Re: KDL-52EX703 6 blinks

6 blinks is Backlight error, Possible problem, Bal board . The board on the right looking from the back.

[budm]

Re: KDL-52EX703 6 blinks

This is LED backlights do it does not use balancer or high voltage inverter circuits.
Can we see straight shot pictures of the backside of the TV?

[holmzy]

Re: KDL-52EX703 6 blinks

thats it it only has 3 boards! the psu measure 316v dc going into the backlight via thin red and blue wires

[holmzy]

Re: KDL-52EX703 6 blinks

What I dont understand is whats reporting the error? also the other thing I noticed when I turn up the backlight the voltage from the psu to backlight does not change. So is the t-con adjusting brightness?

[budm]

Re: KDL-52EX703 6 blinks

The T-CON does control the backlights brightness for the dynamic contrast so they can claim that the TV has very high contrast ratio. I will need to look for the service and training manual for this model next. You can try disconnecting that small connector on the T-CON board to see if the backlights will stay on.

[holmzy]

Re: KDL-52EX703 6 blinks

I got this service manual but its really poor! which t-con cable? I think if I do that the tv does not boot up! I can fiddle in a few hours when my daughter goes to sleep. cheers

[budm]

Re: KDL-52EX703 6 blinks

The small white connector. I did not look at the service manual yet.

[budm]

Re: KDL-52EX703 6 blinks

So they call the main board "BAL", you are right, the service manual is not really good at all. It does not even give the voltage test points. As RJ suggestion, it can be the BAL board per service manual.

[holmzy]

Re: KDL-52EX703 6 blinks

just tried that quickly and i get the 5 flashes indicating t-con issue. the set did not even switch on!

[holmzy]

Re: KDL-52EX703 6 blinks

I managed to a full sw update on that no probs! with the dim backlight!

[holmzy]

Re: KDL-52EX703 6 blinks

all functions on the menu seem to function, and the backlight has no dark spots indicating faulty led. yet 6 blinks and when BL_ERR bypassed dim backlight!

[holmzy]

Re: KDL-52EX703 6 blinks

any ideas? i'm tempted to take t-con out and check for fuse issues but then again it does work! and the led power seems legit at 316v as the caps are labelled 320v / 325v. and it does not drop. the picture itself seems perfect when BL_ERR bypassed just dim.

I dont understand where its getting the backlight error from? is it the t-con? as thats the only thing connected to the screen and av main

[holmzy]

Re: KDL-52EX703 6 blinks

I found dimm and dimm dc on the power board going into av main. can this be bypassed?

[holmzy]

Re: KDL-52EX703 6 blinks

see here

[holmzy]

Re: KDL-52EX703 6 blinks

any help?

[holmzy]

Re: KDL-52EX703 6 blinks

could really use help. the dimming voltage seems to rise to 1.2v to display a half dim screen then screen goes off and v drops to 0.3

[kc8adu]

Re: KDL-52EX703 6 blinks

might be a bad led or 2 in the string.seems voltage is too high.
many i test have vf around 160v.316 on a line with a 320v cap?
look to the led strips.

any ideas? i'm tempted to take t-con out and check for fuse issues but then again it does work! and the led power seems legit at 316v as the caps are labelled 320v / 325v. and it does not drop. the picture itself seems perfect when BL_ERR bypassed just dim.

I dont understand where its getting the backlight error from? is it the t-con? as thats the only thing connected to the screen and av main

[holmzy]

Re: KDL-52EX703 6 blinks

Hi just did some experiments and found:

v on dc = 327v
caps = 350v

when ambient sensor is off and I increase backlight and everything to max the backlight fails to light up and voltage drops to 250/150 range. decrease backlight and it come back and voltage rises again.