Can you dignose from the photo ? . Toshiba 65S2650EV

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

It isn't possible to make a mistake with the AZ431 placement , there is a mark on the board with the flat-curve shape of a transistor.

With regard to NCP1653, I searched ALL the stuff I have and didn't find another, so for now , I will solder new, but lower Wattage R37 5.6K that I found - with big solder blobs to serve as heatsinks, maybe even tiny copper plate to each side. we'll see.

I will test in auto-start mode of course.

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

R37 replaced . measures ~5.6k Ohm in-circuit.

PSU powered : 5VSB = 5.2V
PSU Auto-Started : 5V pin = 300mV. 12V Pin = GND . SHORT ( I didn't realize that before ). No High V

IC3
Pin12 VCC = 6.24V
Pin16 Vboot = 6.04

IC2 - See Image

[lotas]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

Ncp1653

[Davi.p]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

test pin 1 Q10, test in diode mode all big diodes on cold side

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

Ncp1653

What does hysteresis mean in regard to measuring ?

Davi.p : I already did measure Diodes but will do again.
and measure Pin1 of Q10

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

Check this out
D13

[Davi.p]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

i tell you big double diodes, them have 3 inline pins under heat sink

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

OK. will do.

Do you think I should check D13 Diode Out-Of-Circuit ?

[Davi.p]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

i don't think you must focus on them, so you measure short on 12v output? also with ohmmeter? I don't understand which influence can do the pfc circuit (ic2) with standby ps, this is very obscure.. with psu auto started check tension on the bigger electrolitics hot side, check also ic2 pin4 to gnd in ohm..

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

D13 , a W1 diode ( zener ?) on Cold side : I see V in both directions , unlike the others nearby. Looks like D13 is bad and I need to find replacement. see last Photo

Measuring resistance in cold PSU :

12V : ~2K Ohm . rising
5V : 19.6M Ohm . stable
5VSB : ~2.5K Ohm. rising
PS : 4.4M Ohm . stable

IC2 Pin4 (CS) to Pin6 (GND) : 5.6K . stable

Big Capacitors : you mean the Main Capacitors :
This is standard check. I measured now, PSU Auto-Started : 308V

Now I plan to test the Components under the heatsink on Cold side

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

Heatsink out
2 x 60FCT
2 x 100FCT

Any special way to check these Schottky ?

[Davi.p]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

The PFC is not working, this because its vcc is below 8,5v, i told you to measure pin1 q10, i guess it's a bit low, test also pin2, if it's around 4,9v then remove ic2 and test again pin1&2... the idea to remove heatsink is not good because there's no short in the output, forget D13 for now, it is good until you don't test it outside and it's almost 100% ok

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

IC2 is PFC circuit. you say its Vcc is below 8.5V = too low ?
report Pin1 Q10 Voltage, and Pin 2 & if it is ~4.9V - remove IC2 and measure them again.

I'm sorry, but I can't find q10 ? where is it ?

I will solder the heatsink back for testing.

[Davi.p]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

fisrt qst: yes. Check post #165 to find q10

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

IC2 is PFC circuit. you say its Vcc is 4.98 below 8.5V = too low ?
report Pin1 Q10 Voltage 11V, and Pin 2 10.9V & if it is ~4.9V - remove IC2 and measure them again.

So, Q10 looks OK , but IC2 Vcc is very low

I uploaded IC2 Vcc test to be sure I did not make a mistake in the pins

[Davi.p]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

Where it is the fast reply box??

Check the path from q10 to ic2, so D6, Q11, ZD3, R81..

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

Where it is the fast reply box??

what ?

[Davi.p]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

was a message to the staff mainly, don't worry

[Ancient1]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

See Photo
Q11 is a transistor

Resistors near IC2 are OK

[Diah]

Re: Can you dignose from the photo ? . Toshiba 65S2650EV

wow so long threat... you are swiming against the wave...
yours OP photo and this too

yours issue at LEDs back light or at the LED driver baords.. strip the screen out of the set the set will boot with out screen ...and you will see the shadow where it come from.