Hitachi LE55U516 Power supply issue

[102mm]

Hi All . I have a beautiful Recycle Center rescue that has only 5V output and the Main cap stays at 160v even when powered on. From scrolling through this forum on a daily basis I remember that the problem is related to the PWM so i first replaced that IC (IC9301 - A6069H). When that didn't work I replaced (IC9001 - SSC9512S) and it powered on for about 5 min then back to the same issue. I'm close to the problem but I am having a terrible time figuring it out any help would be appreciated.
Images attached, the ICs for the affected area are listed in case you cannot see them clearly
IC9001 - SSC9512S
IC9301 – A6069H
IC9101,9102 – 11NM50N

[budm]

Re: Hitachi LE55U516 Power supply issue

Since you do have 5V STBY then replacing the SMPS IC9301 – A6069H is not the problem.
When you work on TV power supply board, you should look at the power supply board and section out the board to know which section is the standby section, PFC section, main switched supplies section and then find out if you do have Standby power supply to run the main board or not.
you need to do step by step of testing the Voltages:
1) If you do have standby Voltage then check to see if you do have PS-ON command signal (when power switch is activated) from the main board to turn on the PFC and the rest of the power supply or not.
2) If the PS-ON is not present then look at the main board, if it is present then you should have PFC boosted Voltage around 380~400VDC between the two legs of the main cap.
3) Without boosted Voltage, the rest of the power supplies will not be running due to lacking the boosted Voltage even though the PS-ON may be present.

"IC9101,9102 – 11NM50N" That must be an error. Do you mean Q?????

[102mm]

Re: Hitachi LE55U516 Power supply issue

Without boosted Voltage, the rest of the power supplies will not be running due to lacking the boosted Voltage even though the PS-ON may be present.

The PSON voltage is there, 2.8V. when i replaced IC9101 it worked fine for a few minutes, then it started blanking out before it finally stopped working again.

"IC9101,9102 – 11NM50N" That must be an error. Do you mean Q?????

Typo.. Q9101,Q9102

[dick_barton]

Re: Hitachi LE55U516 Power supply issue

One of the pins looks as though it's not soldered and the others could be tidied up.

[102mm]

Re: Hitachi LE55U516 Power supply issue

One of the pins looks as though it's not soldered and the others could be tidied up.

A couple of the pins are not connected and this was not my best soldering.

[102mm]

Re: Hitachi LE55U516 Power supply issue

I measured the voltages on IC9001 - SSC9512S It's getting the following voltages at power on
1- 13v
2 - 13V
3 - .117
4 - 0V
5 - 0V
6 - 0
7 - 0
6 - 0
9 - 0
10 - 0
11 - 0
12 N/C
13 - N/C
14 - .37
15 - .11
16 - .11
17 - N/C
18 - N/C

[102mm]

Re: Hitachi LE55U516 Power supply issue

any idea?

[Andrew F. Ali]

Re: Hitachi LE55U516 Power supply issue

Did you resolder properly those pins that looked improperly soldered??

[jason123]

Re: Hitachi LE55U516 Power supply issue

This is an old post, but because I don't have pictures of the boards, I was hoping someone could leverage info here and help me out.

I have the same model. Works fine, but there are thin vertical lines (not necessarily all the way from top to bottom - sometimes top to 1/3 or 2/3 of the screen) and these are not always there. They seem to come and go depending on the type of picture, colors,...

I always thougth vertical lines are panel issues. Any thoughts?

[jason123]

Re: Hitachi LE55U516 Power supply issue

Ignore please.. I started a new thread here:
https://www.badcaps.net/forum/showth...761#post953761