KDL-60W855B Error Following Firmware Update

[misterduffy]

I'm fuming right now.

Our Sony KDL-60W855B has been in storage for a while and today I retrieved it so we could watch 3D films again. I plugged it in and it worked perfectly. Hooked it up to the PS3, then connected it to the WiFi. It told me a software update was available. How exciting! The update downloaded successfully, then it installed - the rotating arrow was on the screen for a few minutes. Then it went back to the PS3 X-Bar before powering itself off. This was followed by the red light flashing 3 times. Apparently this means main board error. It was working fine. It was on for a good half hour with no problems whatsoever and then suddenly it doesn't work because I updated the software??? Please tell me there is an easy fix for this. The service manual tells me I should be checking voltages on the power board, but it was fine before, I don't see why it shouldn't be fine now. I've tried holding the up arrow and simultaneously pressing the power button, but I just get a relay clicking, and no picture. I don't want to replace the main board for no reason.

Thanks in advance for useful advice.

[Peter_S.]

Hi misterduffy,

I would say it happened by coincidence. Probably because the TV was stored away for some time.

Probably an issue with the power supply - e.g. a faulty capacitor...

Cheers

Peter

[misterduffy]

Well I checked the caps, and some are slightly out of spec. The 820uF one is the worst, reading 780uF, which is about 5% so probably tolerable and unlikely to cause this problem. I can't find any shorted components either. The AC filter cap is fine but I can't check the ESR at the moment. There is nothing visibly wrong with the components and I'm getting standby voltage on pin 27, plus pin 28 goes high momentarily when I try to power on.

The reason I mention the main board is that the service manual specifically states that the red light flashing 3 times means the main board is faulty, so I'm thinking it's corrupted firmware. It is usually the power board that fails first though, because of heat. It seems likely that whichever board I replace first will not be the problem board, so I'll have to replace both. At least I'll have a spare for when the other one eventually fails.

[misterduffy]

Solved the problem (kind of) - it had nothing to do with the update, but seems to be a power board issue. I started a thread on badcaps.net about it for anyone else with a similar problem.