Sony Bravia KDL-60W855B

[brassicGamer]

Hi folks.

So this thing has been in storage for a while and I got it back home yesterday. Amazingly it turned on with no problems... until I opted to install the latest software. The download went fine, then the update process began (a spinning arrow) and it appeared to complete because the picture came back. Then it powered down, flashed red three times in a loop, and wouldn't turn back on again. Attempting to power up resulted in a couple of relay clicks and that's it.

Following the service manual, it indicated that I had a bad main board. I figured this might have been corrupted firmware but maybe it was coincidence. Testing the power board I was getting 3.3V standby voltage on pin 27 of CN6401, plus when I tried to power on I would get 12V supply momentarily on the relevant pins.

Next I removed and tested the filter caps. They all appeared to be within 5% tolerance but I can't measure ESR at the moment so inconclusive. Refitted the caps, installed the board - same error. But when I started measuring voltages at the other end of the connector on the main board, the backlight came on and it suddenly started working! Of course by the time I had screwed the rear panel back on and tried it again it didn't work, but now it's a different problem. The TV powers on but there's no backlight.

I reckon it's the power board, but I wondered if anyone can provide reference voltages for the LD connector? I'm measuring 41.3V on the VLED_VCC pins, but I'm sure I measured 36V earlier.

Thanks.

[nomoresonys]

Re: Sony Bravia KDL-60W855B

Ok, was your update process over wifi?

[brassicGamer]

Re: Sony Bravia KDL-60W855B

Ok, was your update process over wifi?

Yes, as we don't have a router at the moment. It did momentarily work fine post-update after reinstalling the caps.

[nomoresonys]

Re: Sony Bravia KDL-60W855B

Might want to retry the update with a usb drive.

[brassicGamer]

Re: Sony Bravia KDL-60W855B

Might want to retry the update with a usb drive.

I saw that mentioned in the service manual actually - might give it a shot, thanks.

[nomoresonys]

Re: Sony Bravia KDL-60W855B

No problem, hope it works.

[videocentro]

Re: Sony Bravia KDL-60W855B

Hi.
As you explain, I don't think it's a ripple or bad filtering problem.
as your colleagues have advised you, you could via usb, but if as you say, now it does not start perfectly, I do not think the update procedure starts.
In that case the last resort would be to, save the dump fw, rewrite it by extracting the keys-

[nomoresonys]

Re: Sony Bravia KDL-60W855B

That's a possibility, I subscribe to the Karl Childers school of process...easy things first, usb update.

[brassicGamer]

Re: Sony Bravia KDL-60W855B

One more question. If the screen isn't working, how am I to initiate and monitor a firmware update? I've downloaded it onto the USB stick, plugged it into to a socket on the TV and turned it on. According to the service manual it will automatically update, but I don't know if it's actually doing that or not.

[William1967]

Re: Sony Bravia KDL-60W855B

Use an USB drive with control led so you can see there is activity.

[nomoresonys]

Re: Sony Bravia KDL-60W855B

Ok, this one seems to require you to use your remote:

https://www.sony.co.uk/electronics/s...loads/00016378

[Diah]

Re: Sony Bravia KDL-60W855B

Hi folks.

So this thing has been in storage for a while and I got it back home

But when I started measuring voltages at the other end of the connector on the main board, the backlight came on and it suddenly started working! Of course by the time I had screwed the rear panel back on and tried it again it didn't work, but now it's a different problem. The TV powers on but there's no backlight.

Thanks.

from yours first post i read story of issue (set was lie down in storage, and while you was testing and measurement on sockets it start working.. )

so before you running after firmware or got lost by causing other damage.. i suggest you take it in part and resolder all sockets and check cable.. i think you dont facing parts fault... but bad storage effect which involved only on soldering.

[nomoresonys]

Re: Sony Bravia KDL-60W855B

I think best policy for update is always try to do it over a wired connection, bad things can happen over wifi, might not be what happened but it's my hunch that it went wrong. Good point Diah, it sure could be the problem.

[brassicGamer]

Re: Sony Bravia KDL-60W855B

i suggest you take it in part and resolder all sockets and check cable.. i think you dont facing parts fault... but bad storage effect which involved only on soldering.

Well now I don't know what to say. While testing earlier to see if there was sound, the TV went into protection mode and flashed red 4 times, which means 'bad panel'. This immediately made me suspicious because that's two completely different problems even though no changes have been made.

So I persisted. Following your advice I removed all boards, inspected for cracked / dry solder joints or debris / corrosion, cleaned all connectors and plugs, reseated everything and tried again. The error had cleared, but still no backlight and then after about 12 seconds it went back to the error again. However, I unplugged the power and cleared residual power by connecting and disconnecting the cable between the main board and the power board (the relay clicks on and off every time you plug it in, until it stops clicking to indicate the power has dissipated). On most devices you can power on to achieve the same thing, but that method doesn't work here.

I plugged the power back in and waited 20s, then powered on. It works. The TV was on its side at this point so I tried moving it - sure enough it cut out and errored again. I repositioned the TV, followed the same procedure as before and it works again. So there is some kind of electrical issue related to physically unstable component(s) which I have been unable to find. This could be a pain in the butt if I want to mount it back on the wall though! I haven't moved it since and it's still working an hour later.

I don't know what to tell you guys. It's a weird problem. One thing is for sure, that the flashing red lights are only what the TV thinks is the problem based on signals, not what the problem actually is. Had I taken it literally, I could have purchased a new power board and main board by now and be no better off.

I guess persistence and trying lots of different things pays off. It's not fixed, but it's not broken either.

EDIT: tried firmware update but the previous update was successful, it seems, so no update required.

[Diah]

Re: Sony Bravia KDL-60W855B

[COLOR="Red"]I plugged the power back in and waited 20s, then powered on. It works. The TV was on its side at this point.

this will complete the story of bad storage....if you were sure you did inspect every things good... then go to take the screen apart and rework all LED BL sockets.. soldering ... but its risky work... don't do it alone and be sure you have tools and space. as yours set when stand on side it worked. this had nothings to do with firmware or any failed parts... only LED BL Sockets cable

[brassicGamer]

Re: Sony Bravia KDL-60W855B

this will complete the story of bad storage....if you were sure you did inspect every things good... then go to take the screen apart and rework all LED BL sockets.. soldering ... but its risky work... don't do it alone and be sure you have tools and space. as yours set when stand on side it worked. this had nothings to do with firmware or any failed parts... only LED BL Sockets cable

Might wait until I get my hot air rework station rather than risk the soldering iron

[Diah]

Re: Sony Bravia KDL-60W855B

Might wait until I get my hot air rework station rather than risk the soldering iron

ahh okay.. i thought you are going to buy other set lol..
i do like this 3D Sony W series i got one defect from ebay 2016 65W955B till now its worked at my young daughters family.. however it got hits many time by her kids but still fighting LOL

[nomoresonys]

Re: Sony Bravia KDL-60W855B

Ok, that's what it looks like, if not a bad solder then probably loose connection, you already had the latest firmware after your wifi update so that's probably why the usb one didn't go thru.

[brassicGamer]

Re: Sony Bravia KDL-60W855B

Just wanted to add a final note to this, because I got the same error again after moving the set (it will soon be mounted on the wall). It seems quite a specific problem, but I hope it might be able to help someone else.

It's definitely to do with the backlight system because this time I was able to verify that there is picture (using the torch method) and there is audio. I use the following procedure to fix the error although it does unfortunately mean removing the rear panel:

- Power off unit.
- Unplug from mains.
- Disconnect the cable that connects the main board to the power board.
- Reconnect - you should hear a click from the relay.
- Repeat until the relay stops clicking.
- Reconnect power.
- Wait 30s for capacitors to charge.
- Power on.

This has worked consistently for me but it still doesn't tell me what the actual problem is. It seems to me from the symptoms that it's capacitor related and therefore a power board problem. If I had another board to swap then I would know, but I can now test ESR so maybe that will turn up a bad cap.

[brassicGamer]

Re: Sony Bravia KDL-60W855B

The actual final note is that I purchased a new power board and that fixed the problem. Go figure.