lg philips plhl-t707a eay36781302 no 5v

[jones]

i want share this information about this board plhl-t707a. may help someone or some one will help me, cuz i cant find replacement board
this power board it will give <2v beside 5v on the connector p201 pin 3 and 8.
if the connector p201, p202, p402, p401, p205 disconnected then connected the board to the power will take more than 5 min for the standby voltage to reach the 5v (all the caps, doids, fuses, resistors tested good). then i connected the main board and other plugs to the power board the tv will turns on and works fine. so must be something charging slow or needs to get warm for the board to get the right 5v
i unplugged the tv and and give it it 15min plugged it to the wall tv wont turns on, and i got 1.9v beside 5v, i warmed up the u502 ic chip (ice3b1565j) tv turns on from first try, and got strong 5v
i m going to order the this chip and will update if it fix the problem
if someone has any other suggest will be great
thx

[jones]

Re: lg philips plhl-t707a eay36781302 no 5v

http://html.alldatasheet.com/html-pd...CE3B1565J.html
this a ICE3B1565J Datasheet and it shows this chip controlling the 5v.

[petehall347]

Re: lg philips plhl-t707a eay36781302 no 5v

have you tried fresh solder ?

[budm]

Re: lg philips plhl-t707a eay36781302 no 5v

Did you try replacing those startup/running caps, C506, 507, 508, 510, 511?

[jones]

Re: lg philips plhl-t707a eay36781302 no 5v

Thanks for the replay,
No cracks on solder,
I just changed the big capacitors ac to dc, the other capacitors all of them look good, that will be the next if the new ic chip didn't fix the problem

[budm]

Re: lg philips plhl-t707a eay36781302 no 5v

Bad cap can look normal, especially those small startup/running cap.
You can try by just heating those caps I pointed out to see if it make the power supply starts up.

[jones]

Re: lg philips plhl-t707a eay36781302 no 5v

budm you the man, it was a bad caps i changed a C506, 507, 508, 510, 511 as you suggested. and tv works

another question plz. i have other lg eax61432501 power board that has a problems clicking on off, the big resistors for vs or va are good reading not open.
can i keep posting here or i have to open new one? thank you

[budm]

Re: lg philips plhl-t707a eay36781302 no 5v

Thanks for the follow-up.
You should start a new thread with good clear pictures, make and model number of the TV, etc. the more details the better.

[Don Brotherson]

Re: lg philips plhl-t707a eay36781302 no 5v

I have replaced the caps, the 7-pin regulator, Q103, and another zener diode. While removing ZD100, I realized it had cracked in half, making any markings unreadable. Does anyone know the value of ZD100 or where I might find it ?

[budm]

Re: lg philips plhl-t707a eay36781302 no 5v

I have replaced the caps, the 7-pin regulator, Q103, and another zener diode. While removing ZD100, I realized it had cracked in half, making any markings unreadable. Does anyone know the value of ZD100 or where I might find it ?

Is this the exact matched (P/N, ETC.) to your board?
http://www.shopjimmy.com/lg-eay36781...upply-unit.htm

[budm]

Re: lg philips plhl-t707a eay36781302 no 5v

Typical value for the Zener is 3.3 ~ 3.6V range, it is connected in parallel with the Source resistor of the power MOSFET.