Toshiba 37" inverter board failure

[whatusername]

Re: Toshiba 37" inverter board failure

ok so i ran a test like budm had the other guy do on a different set of jumping the 12v wire i went from power supply 12v to tcon fuse and the tv showed words on the screen like it should. so im thinking maybe i should just leave the jumper wire there but i am looking for a good location to solder to.. i dont want to dolder from power supply to tcon directly anyone got any ideas where i can get 12v from main board and where on the tcon i can solder it to? or even if i just jump trace on main board that would work too.. just need location ideas

[whatusername]

Re: Toshiba 37" inverter board failure

ok just learned something new.. apparently i shouldnt jump straight to the fuse cuz the tv was on when i was holding jumper wires in place and when i had them unplug the tv it shut off normally but i then i decided to test fuse on tcon before i solder and it has blown fuse.. lucky i have a spare tcon for this tv

[whatusername]

Re: Toshiba 37" inverter board failure

i rather fix this tv correctly than jump it to be honest.. so i await input as to what to do next

[budm]

Re: Toshiba 37" inverter board failure

"both of this chip pins agnd and pgnd give me 1.3 to the vias in 200 ohm setting so reading is .1 ohm" Please verify this for me, measure the resistance between those Vias on that big trace and chassis ground to see what you get.

[whatusername]

Re: Toshiba 37" inverter board failure

ok will do it now

[whatusername]

Re: Toshiba 37" inverter board failure

ok i get .1 ohms between that trace and chassis ground so it seems to be a neg trace or severely shorted

[budm]

Re: Toshiba 37" inverter board failure

It has shorted circuit. Remove that white LVDS cable from the board to see if shorts is still there, be careful on those small wires.

[whatusername]

Re: Toshiba 37" inverter board failure

yes it was still shorting then i decided to remove every plug and test and no short then as i plugged them back in 1x1 it came back when cn91 was plugged. that is coming from power board pic attached


decided to test what pins on the cables shorted and from left to right pin 3 and pin4 showed ground pin 3 reads it is a gnd and pin 4 reads power lcd but then it reads gnd under it but i dunno if its from the jumper or if that pin is lcd pwr gnd but they do have continuity even with cable unplugged

[budm]

Re: Toshiba 37" inverter board failure

I am so glad you show me that picture of CN91, the '12VCD' is the +12V for feeding the LCD panel. it looks like pin 1 (white arrow and pin 2 are tied together (please verify) and go back to the power supply board, so the switched 12VLCD is on the power supply board.
Good clear picture of the power supply board top and bottom side, and especially where that '12VLCD' connector is. I wish I had the board in front of me, I would have seen that connector.

[whatusername]

Re: Toshiba 37" inverter board failure

that connector in the pic is not cn91 it is of the power supply board where the cable for cn91 connects

[budm]

Re: Toshiba 37" inverter board failure

Good clear pictures of the power supply board next, top and bottom.
SJ does not have pictures of the bottom side of the board.
http://www.shopjimmy.com/media/catal...sj75011638.jpg
We'll need to find the service manual next.
We will try to locate the shorts on that 12VLCD lines next.

[whatusername]

Re: Toshiba 37" inverter board failure

ok here u go

[whatusername]

Re: Toshiba 37" inverter board failure

i downloaded the sm from elekto tonya or whatever it is but it keeps saying i need zeus and only shows me HTML pages

[budm]

Re: Toshiba 37" inverter board failure

I was never able to setup ZEUS to work.
So right now, just the power supply board by itself, if you put the probe between the 12VLCD pins and the GND pins next to them, it will show <1 Ohms?
I cannot see the traces leaving the 12VLCD to know where it goes to, I expect it may have shorted out capacitor, or may be Zener diode. You will have trace out the 12VLCD lines.

[whatusername]

Re: Toshiba 37" inverter board failure

yup it grounds out

[tom66]

Re: Toshiba 37" inverter board failure

Regarding Zeus:-
I had to use Win XP virtual machine & IE7 plus install Autodesk Viewer (don't use the one included in the install setup)

[whatusername]

Re: Toshiba 37" inverter board failure

thanks tom but unfortunately im running windows 7 so i cannot use it

just saw u said xp vr i am downloading it now

[budm]

Re: Toshiba 37" inverter board failure

Hi Tom, which viewers do I need to use? DWF or DWG?
http://usa.autodesk.com/support/viewers/
So for me to see the sch, I will use the I.E. to open the downloaded file (which one from TOSHIBA)?
I see lots of *.html files, some I can open for example:
!spec.html to see the spec sheet, but the diagram, it does not show anything.

[whatusername]

Re: Toshiba 37" inverter board failure

Dwf bud

[tom66]

Re: Toshiba 37" inverter board failure

DWF Desktop Viewer.
If anyone wants, I'll upload my VirtualBox VM with Zeus pre-installed and setup, but it's about 10GB so will take some time.
You just need VirtualBox to run it, the free version works fine.