Sony shorted screen,fixed

[martino]

Hi,thought I would post this in the hope it can save some tv's.

Sony KDL-42ex440,completely dead,no reaction on buttons etc,as if main fuse is blown.
Disconnected LVDS cable to t-con,tv comes alive,no picture of course.
Reconnect LVDS,disconnect one of two ribbons to panel,tv comes alive with halve screen,other side white.
Reconnect that ribbon,disconnect the other ribbon,tv completely dead again.

Looked at small PCB that's attached to panel along the edge,found that the 3 larger capacitors(one by each tab) measured 2.6 ohms.Suspected them to be in parallel.
Removed the capacitor closest to the ribbon cable connector,short gone and tv works perfectly fine again.

Hope this will help somebody

[budm]

Re: Sony shorted screen,fixed

Nice work locating bad cap.

[martino]

Re: Sony shorted screen,fixed

Lol,super easy to find. I posted this more for awareness,as in "don't give up on panel too soon"
I fixed a few this way,some samsungs etc. Never had luck on LG with this.

It would probably be a good idea to replace that cap,so far I just remove them,never had one come back yet.

[syaoran123]

Re: Sony shorted screen,fixed

Thanks for sharing. Were there any visual signs of damage? What models have u tried this on?

[martino]

Re: Sony shorted screen,fixed

Thanks for sharing. Were there any visual signs of damage? What models have u tried this on?

Can't remember the models,it's wide spread.
When in diagnosing I get halve screen results,I then measure all caps on those narrow boards. Been lucky with this often enough to make it an effort
No signs of damage to caps,they just measure very low ohms.

[mmartell]

Re: Sony shorted screen,fixed

Nice save and thanks for posting it.

[budm]

Re: Sony shorted screen,fixed

BTW, the failure mode for those MLCC is shorts or bad leakage resistance.

[ivtec]

Re: Sony shorted screen,fixed

Thanks Martino good job, that's why i say Badcaps forum is the best Forum ever.

[ReeceyBurger123]

Re: Sony shorted screen,fixed

Nice work buddy, I recently had a 32" Sammy panel shorted ceramic and smd transistor changed with ones off a smashed screen (same model) and sorted it seems to be newer sets having his issue. Done a vid on it.

[CapLeaker]

Re: Sony shorted screen,fixed

good detective work!