Toshiba 32PB10E No power

[s_henya]

Hey guys,

After a pretty bad weather weekened i got this lcd in,

With no power, not even the STBY led.

Opened it up everything looks perfect,

(tested elec' caps and fuses for now)
main filter cap: Samyoung KMF 450V 100uF showed 96uf 0.4ohm (pretty high ESR) is it still usable?

PSU: PSIV161C01T
MAIN: V28A001308A1

I got 5v on the output of the psu, but no STBY led.

I need to verify if the mainboard is bad or the PSU.

I want to force start the PSU and i need some guidance.

Which pins do i need to short?

And another question, i can see 2 large cubes FL750 FL755 on the mainboard

by the FL i think they are fuses,

but i can see the have many legs, how do i test them?

[CapLeaker]

Re: Toshiba 32PB10E No power

Force the PSU:

Unhook the main board from the power supply. Take a 1k Ohm resistor and jumper 5V STBY to PSon. Take another 1k resistor and force the back light on by jumping 5V to BLon. Plug it in and all voltage rails should be up and the back light should be on.

Check main board:
5V STBY voltage from the PSU is always on. Take the resistors off the PSU and plug the main board back in. Make sure 5V STBY is getting to the mainboard. Once you hit the power button on the TV, the main board should send a voltage back to the PSU to turn on all the power rails. Probe the PSon pin and see what it does.

[s_henya]

Re: Toshiba 32PB10E No power

CapLeaker thank you!

I used 2 1k resistors:

Between pin 5 (5v) to pin 8 (Power_TV)

Between pin 6 (5v) to pin 11 (BL_ON)

I now have addional voltages, and the backlights are on

PIN1 GND 0
PIN2 13V 12.82
PIN3 13V 12.82
PIN4 GND 0
PIN5 5V 5.12
PIN6 5V 5.12
PIN7 GND 0
PIN8 Power_TV 4.358
PIN9 AC_DET 0
PIN10 GND 0
PIN11 BL_ON 4.86
PIN12 EX_DIM 1.293
PIN13 IN_DIM 1.291
PIN14 STATUS 0

this means i have a fault in the mainboard?

should i preform a load test?

i want to make sure before i give up
(i had a feeling that the cable box that was connected by HDMI cable burnt the mainboard in the storm) because even though i had 5v STBY voltage from the PSU the STBY led in the panel didn't light.

[CapLeaker]

Re: Toshiba 32PB10E No power

O.k. Now you take the resistors off, hook up the main board and everything else back up, turn on the TV and measure pin 8 PWR TV. If there is nothing (and I think there will be nothing) the problem is the main board.

So I'd be looking hard at the fuses on the main board first, before you decide to chuck it.

[s_henya]

Re: Toshiba 32PB10E No power

I removed the resistors, and plugged the psu to the mainboard,

tested pin 8 and got 0vdc.

i there any need to preform a load test to the psu to verify it's not failling under load?

I didn't manage to find a replacement mainboard in aliexpress, ebay or shopjimmy

So any testing inputs on the mainboard will be great!

By the way i asked about FL750 FL755 what are they?

[budm]

Re: Toshiba 32PB10E No power

FL is more likely the same as Ferrite Bead which is the small inductor for filter, it should have very low resistance.

[s_henya]

Re: Toshiba 32PB10E No power

Any more test points on the mainboard before i give it back to my friend?

[CapLeaker]

Re: Toshiba 32PB10E No power

You don't need a load test yet, it doesn't take much to make a LED blink. I am not able to source a schematic. So I guess you would have to trace the STBY 5V rail on the main board.

[s_henya]

Re: Toshiba 32PB10E No power

Solved!

Googled the main board and bought if from Poland.

Quick replacement and the TV is working again!

[budm]

Re: Toshiba 32PB10E No power

Thanks for the follow-up.

[CapLeaker]

Re: Toshiba 32PB10E No power

sweet!

[Prageeth]

Re: Toshiba 32PB10E No power

Can you please tell me the panel number. I have the same TV. It has a panel problem.

[s_henya]

Re: Toshiba 32PB10E No power

I dont have it anymore it was returned back to its owner after repair.

[PSX04]

Re: Toshiba 32PB10E No power

I had the same issue so i will try your solution ... Wait for my result ��