Help fixing a rescued sony kv-3400

[soviet9922]

A wile ago a friend of mine found a sony KV-3400 on an abandoned building, who knows how many years was there.
After managing to move that beast of a tv "55 Kg" to my apartment and then to my workbench xD, started to check it out.

The TV have some oxidation on the RF shields and on the adjustment trimmers, but lucky it was not exposed directly to the elements so there's was no water in it.
The plastic casing is in bad shape but the internals are kinda OK.

First replaced the power cable the original was in bad shape.

Then turned it on after pressing the power button I can hear high voltage kick in, my probe meter goes up to 30K +, then after a couple of seconds it will shut down, then after a couple of minutes i can hear clicking coming from the power supply.

Could love to get this monster tv fixed will document the process here.
Open to any suggestions about this issue kinda lost where to start ?.



On the abandoned building sad big tv xD


But now at home it don't look nearly as bad.


The good thing is that the service manual was easy to find love the internet archive
https://archive.org/details/sony_kv-340 ... s_gp-2a_sm

[soviet9922]

up

[jd213]

Maybe start by checking the voltages on the board as shown in the service manual

[tongshadow]

If you're getting High Voltage then at least you have the B+ voltage and the horizontal output transistor is fine.
What you describe sounds like Sony's IK circuit protection, which activates when the neckboard's transistors or resistors have failed. What voltages are you getting on the RGB pins of the neckboard?
And because the TV is in such poor shape, assume that cracked joints and/or oxidized contacts can cause of issues as well. Carefully inspect the boards.