Sony Bravia 55HX820 - 4 times blinking red standby led

[androripara]

Hello everyone,
i am trying to repair a Sony KDL-55HX820 led TV which is throwing error code 4 (standby led flashing four times).

I followed the troubleshooting flowchart at page 69, and between pin1 and pin7 of CN6002 i am reading 1.91V so i guess i can rule out the B Board as the culprit.
Before ordering new G* Boards (by the way, should i change both? it is not specified in the manual) i wanted to try and do more advanced troubleshooting since i've read in other threads people resolving their problems on the 46/55 HX 820/823/825 models by replacing the Samsung led driver SSL4055_2E4A and/or T-CON board, which are apparently prone to failure.

Attaching:

• Pictures of the different boards
• Relevant manual

Could someone more knowledgeable help me?
Thanks

[nomoresonys]

Re: Sony Bravia 55HX820 - 4 times blinking red standby led

Well the manual says backlight driver board, replacements are usually not too expensive.

[zomi]

Re: Sony Bravia 55HX820 - 4 times blinking red standby led

try strap bl err board on psu to ground
See if it turns on ?
worth a try

[androripara]

Re: Sony Bravia 55HX820 - 4 times blinking red standby led

Well the manual says backlight driver board, replacements are usually not too expensive.

It does, but manual suggests replacing first the G* Board, which i can't find at the moment, however i've already ordered the led driver and t-con boards, since they were cheap, it is going to take a while for them to arrive.
Just wanted to ask if there is anything i could do at the moment, maybe i won't fix the TV right away but i will surely learn something new since i've never done any kind of hardware repair!

try strap bl err board on psu to ground
See if it turns on ?
worth a try

Thanks for your reply, could you please be more descriptive? i am really new to all of this!

[lotas]

Re: Sony Bravia 55HX820 - 4 times blinking red standby led

Check the fuses.

[zomi]

Re: Sony Bravia 55HX820 - 4 times blinking red standby led

If you take the bl err wire and ground it

it shoudl let you power tv on and see whats happening.

its worth trying

[androripara]

Re: Sony Bravia 55HX820 - 4 times blinking red standby led

Thanks everyone for your replies, as i said i'm a complete beginner in electronics so i will ask very basic things that you might take for granted.

Check the fuses.

I checked both fuses with a multimeter, they have continuity and around 3-4 ohm resistance. I guess that means they are ok? Should i then rule out the led driver board?

If you take the bl err wire and ground it

it shoudl let you power tv on and see whats happening.

its worth trying

If i understood correctly, i should short it like in the picture i'm attaching, then plug in the connector and turn on the TV? If that is the case, i think it's a bit too difficult for me since i don't have such a fine pointed soldering iron. Is there some other method i could try?

[nomoresonys]

Re: Sony Bravia 55HX820 - 4 times blinking red standby led

Do this, check voltages 1-14 of CN2001 on backlight driver board, report voltages here.

[zomi]

Re: Sony Bravia 55HX820 - 4 times blinking red standby led

You take the pin out of the plug and you can then just tape to the back of the tv to ground it.
used to do with ex series sony when they had similar problems.

[androripara]

Thought of posting an update: turns out it was a faulty LED Driver board, replaced it and now everything works flawlessly, didn't really bother with trying to repair it since it was only 8$ shipping included!

thanks everyone!

[nomoresonys]

Glad to hear it, thanks for the followup, appreciate it.