32lg3000 sound ok but no picture

[nbdy]

Re: 32lg3000 sound ok but no picture

Could this be the bead :

http://www.ebay.com/itm/BI-TECH-1206...AAAOxy~ilSRf4N

[budm]

Re: 32lg3000 sound ok but no picture

That should work. So did you check the resistance at the output side of the inductor? It burnt up like due to shorted circuit some where especially when the MOSFET was also damaged.

[nbdy]

Re: 32lg3000 sound ok but no picture

Well I have checked mass of the components,all seem to be OK ...

Could it be be cause of washing the flat cables with alcohol (didn't wait to long) that the bead and the mosfet blown up ...

The resistance on the output side ???

[budm]

Re: 32lg3000 sound ok but no picture

"The resistance on the output side ???" OK, make it easier to understand, just check the resistance between GND against each end of that burnt up inductor.
The MOSET is being used as a switch so if the load is shorted then the MOSFET and the inductor will be damaged.

[nbdy]

Re: 32lg3000 sound ok but no picture

The first end is 325 ohm,and the second OL ...

The first one is connected to C400,C401 and the second to PANEL_POWER C1156,and pin 5,6 on the MOSFET

[budm]

Re: 32lg3000 sound ok but no picture

325 Ohms? I expect it to be in 1000 of Ohms with T-CON board in place, and OL without the T-CON.
Is that the reading without the T-CON board connected?

[nbdy]

Re: 32lg3000 sound ok but no picture

The readings are the same with/without the T-con boar (2 of them,old and new)

The first end is 325 ohm,and the second OL ...

The first one is connected to C400,C401 and the second to PANEL_POWER C1156,and pin 5,6 on the MOSFET

Could it be because of alcohol cleaning the pins (to fast connect after)

[budm]

Re: 32lg3000 sound ok but no picture

If the T-CON board is not connected and you still read 325 Ohms then one or more of those caps has leakage resistance, cap block DC so it should show open circuit (very high resistance (leakage resistance). I would remove the cap and test to see which one is showing 325 Ohms.

[nbdy]

Re: 32lg3000 sound ok but no picture

Ok,you think of C400 and C401 ???

I removed the bead and the mosfet and the measures are without them but with and without the t-con boar connectet only on MB,nothing else is connected (PSU,Screen)

[budm]

Re: 32lg3000 sound ok but no picture

I just notice something, are the 1.3K resistors R407, 408, 433, 434 installed on your board? That may explain the 325 Ohms reading.

[nbdy]

Re: 32lg3000 sound ok but no picture

Yes the are on board

[budm]

Re: 32lg3000 sound ok but no picture

OK, the 325 Ohms reading is normal then. I would replace MOSFET and the inductor and then power up the TV without the TCON board in place to make sure the switched Panel Voltage is working first.

[nbdy]

Re: 32lg3000 sound ok but no picture

OK,I have to order the parts ...

Now I'm thinking of ordering (100 pcs beads and 5 mosfets - 16$) and the board 22$ (refurbished)

What should be the better solution

[budm]

Re: 32lg3000 sound ok but no picture

Well you need yo get the switched panel Voltage working first, the put in the TCon board but without the ribbon cables between the TCon and the panel connected to verify that the switched panel Voltage is still Ok, then connect the cables between the TCon and the panel back in to see if you will get the working pictures on the screen.

[nbdy]

Re: 32lg3000 sound ok but no picture

YOu mean without the bead and the mosfet ???

[nbdy]

Re: 32lg3000 sound ok but no picture

Found the bead from another board,just the mosfet try to get tomorrow here in croatia

[nbdy]

Re: 32lg3000 sound ok but no picture

Hi again, finaly the parts came to me ...

But now I have only a 3 time flashing red light,and then no light ...

The lamps are working (see them from the back holes) ...

It is the same with and without the t-con board (the screen flats are not connected)

[nbdy]

Re: 32lg3000 sound ok but no picture

Bought a new main board,but the result is the same ...

3 x flashing red,and the backlight on,but no picture,any further help ..

rechecked the power supply,all voltages are present ...

same with new/old t-con board ...

same without the t-con board ...

thx