plasma tv help

[envme123]

hi all, i have a dynex plasma dx-pdp42-09. i recently had a small roof leak and like literally 2 drops of water went into the tv right down the middle. poof not working anymore. i opened up the tv and found 2 of the little buss bars on the power supply roasted. to check the tv i jumped out the 2 buss bars and tried to test it. when i plug it in i get a click noise and the led on the front of the tv lights up red. there is also a green led on the power supply that lights up. however when i try to turn on the power nothing happens. i have tested the power supply and only have power on the 5vsb test point. i am fairly apt at electrical testing. any suggestions. thanks I do have a good general understanding of repair and testing but not an expert by any stretch.

 

[duffy]

Another guy on here had the same problem with burned buss bars in his plasma TV. Check back through the postings and see if you can find that item, it was from sometime earlier this year.

Also make a visual inspection of the power supply caps - someone else with the same problem on the same set found this useful -
https://www.fixya.com/support/t10523200-dx_pdp42_09_won_39_t_power_up

And if you have to replace the whole supply, you can get one off eBay for $68 -
**broken link removed**

 

[envme123]

Thanks for the reply. I couldn't find that post about the buss bars. I have checked the caps and all looks ok. I am relatively confident that my repairs to the power supply are good enough for testing . My question I guess really is, what am I looking for in a wake up signal for the tv? Is that 5v source the only thing i shouuld have when the tv is off? If so, what yells it to turn on the rest of the power?
I have that 5v out of the power supply and its getting to he main, but that's is. When I try to power it up via the button or remote nothing, no clicks no anything. Idk if that means my main board is screwed or what. Thx

 

[duffy]

Do you have a schematic? Plasma TVs typically have very complex supplies with +190V, +60V, -180V, +12V, etc. and the start sequence on this one may involve checking voltages before activating the drivers. I would stick a scope on anything that looks like it's coming from the controller to switch on the main power to see if there's any activity. If it looks like it is trying to switch it on, and then shuts off again, check to see which voltage is not coming up during that period, then troubleshoot that section.

Also, a Dell plasma has a switched +3.3V for the main CPU - if yours is like this, it will either need that 3.3V constantly available or need it switched on by a separate +5Vsb-powered controller to get the processor up and running.