LCD TV won't turn on. LED keeps blinking

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

red lead for the 12th pin its ok. and black pin for? i didn't get it

like this?

[vinceroger69]

Re: LCD TV won't turn on. LED keeps blinking

the large capacitor you have been testing 325 v on use the negitive side of that capacitor for your black multimeter test lead,

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

0.85v in vcc and the - cap

board is not connected to the tv. but powered and switched on

[vinceroger69]

Re: LCD TV won't turn on. LED keeps blinking

ok thanks now we need to trace back and see why the voltage is so low bear with us as im still leaning myself so maybe dick or budm can advise what too check next as i cant seem to fnd a schematic/service manual for your set

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

is it the problem with IC?

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

ok thanks now we need to trace back and see why the voltage ..........schematic/service manual for your set

thank you vinceroger69

[vinceroger69]

Re: LCD TV won't turn on. LED keeps blinking

with the tv turned off and unplugged what RESITANCE do you get between the vcc pin and ground pins like you marked in your picture .

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

310 k ohms

[dick_barton]

Re: LCD TV won't turn on. LED keeps blinking

Can you post clear bright pictures of the top and bottom of the power supply board. Take it out into the sunlight and take the photo's. It's difficult to identify anything on the boards.

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

image is too large. may i upload as a winrar?

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

image is too large. may i upload as a winrar?

pictures

[dick_barton]

Re: LCD TV won't turn on. LED keeps blinking

Why is there a piece of wire connected from R9 to G of mosfet?
There are quite a few solder joints that do not look very good.
I see that some of the mosfets have been taken out. Have they been checked using your ohm meter

Have you also tested D8, ZD3, D12, Q4, ZD3 and D4 using your ohm meter?

I think it would be best to order a replacement power supply.

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

Why is there a piece of wire connected from R9 to G of mosfet?
There are quite a few solder joints that do not look very good.
I see that some of the mosfets have been taken out. Have they been checked using your ohm meter

Have you also tested D8, ZD3, D12, Q4, ZD3 and D4 using your ohm meter?

I think it would be best to order a replacement power supply.

solder joints are now ok. i checked them.
i replaced all components .
the wire is now not on the board. it soldered by me.
i soldered the wire because Q1 is not connected to the GND i thought the path is missing. but the wire did not solve the issue

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

i tested ZD3, D12, Q4, ZD3 by removing

they are working...

also D8 is working

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

Thnk you dick_barton for the advice.

[ReeceyBurger123]

Re: LCD TV won't turn on. LED keeps blinking

IMO seems like the SMP Ic is not running.

[dick_barton]

Re: LCD TV won't turn on. LED keeps blinking

Unfortunately I don't think sahan14 is familiar with repairing which is why I suggested a board replacement would probably be the best course of action.

[vinceroger69]

Re: LCD TV won't turn on. LED keeps blinking

I have too agree with you now too i would source a replacement board.

[vinceroger69]

Re: LCD TV won't turn on. LED keeps blinking

psu schematic

[sahan14]

Re: LCD TV won't turn on. LED keeps blinking

I can replace the IC. yes.. I don’t have good knowledge with repairing. but i can understand what you are telling..