Re: LG 55la965w Black screen no 3.3v INV ON signal
Hi folks ,
Just an update to let you know how i went on with this problem.
The mainboard went in the oven after applying no clean flux .
380 degrees monitered carefully with oven thermometer, had to keep fiddling with oven thermostat, increased temperature to 410 over the space of 10 mins.
I could see through the the glass door that the solder looked shiny like a fresh solder joint.
turned off the oven, opened the door and let it cool down.
replaced board in TV and lo and...
tiprat63
Member
Last Activity: 06-12-2021, 05:26 AM
Joined: 05-13-2020
Location: Pontefract
-
Re: LG 55la965w Black screen no 3.3v INV ON signal
I checked the T con voltage when TV turned on, No 12v on supplementary power connector at the fuse.
I checked the power at the ultra hd board, which comes from power supply board. 12v, but no 12v coming from HD board to T con.
sounds like the main board is gone from reading .
What do you think , main board or the ultra hd board, or both ?Leave a comment:
-
Re: LG 55la965w Black screen no 3.3v INV ON signal
Sorry just realised hat pic was upside down too.
here are more , but at the mo i have very low light levels so had to use a flashlight to take pics.
I will take better ones tomorrow if needed .
many thanks...Leave a comment:
-
Re: LG 55la965w Black screen no 3.3v INV ON signal
[attach]219573[/attach]
Hi , here should be a picture of the back of the TV
I don't have the power readings / voltage readings from the power supplt to main board at hand.
I tested the led strips with an led tester and they were both around 230v.
The DRV on 3.3v was missing and no pdim or Adim as mentioned.
I depinned the DRV on and both DIM wires , as i read a similar problem on this forum that was very informative, I think it was budm that was assisting someone....Leave a comment:
-
Re: LG 55la965w Black screen no 3.3v INV ON signal
Hi , here should be a picture of the back of the TV
I don't have the power readings / voltage readings from the power supplt to main board at hand.
I tested the led strips with an led tester and they were both around 230v.
The DRV on 3.3v was missing and no pdim or Adim as mentioned.
I depinned the DRV on and both DIM wires , as i read a similar problem on this forum that was very informative. I did order some 1k resistors to do the test mentioned in the post .
I thought...Leave a comment:
-
Re: LG 55la965w Black screen no 3.3v BL ON signal
Thanks for the reply , i shall post pictures you requested later on.
With the power readings .
Sorry about saying inverter board, i've been reading so many manuals of different TVs . I should say LED power board, This is seperate to the main power board,Leave a comment:
-
Re: LG 55la965w Black screen no 3.3v INV ON signal
i like information to diagnose problems my self, hard facts, not hearsay. I will check all voltages again tomorrow and list the points they were taken on the board/s .
Hope fully some one will be able to assist.
Thanks.Leave a comment:
-
Re: LG 55la965w Black screen no 3.3v INV ON signal
Hi and thanks for that info.
There is no LOGO flashing on turn on .
24v to inverter but no BL ON signal
Any ideas?Leave a comment:
-
LG 55la965w Black screen no 3.3v INV ON signal
Hi , i would really like some help to diagnose and repair this TV.
I'm not an expert but have knowledge of electronics, i actually work on high pressure cleaning equipment. I have various pieces of test equipment, but no oscilloscope.
I'll try and keep it short as to what happens and what i have tested.
Tv was working fine , then just went off.
plug it in and the red standby led is on solid.
turn on TV, the red led blinks 3 times then goes out.
No picture or logo comes on the screen.
Turn the Tv off and back to solid red... -
Re: New Members - please post your introductions here
Hi , just joined and having a nosy about seeing what all the buttons do .
Service engineer for high pressure cleaning equipment , ie pressure washers .
I've always had an interest in electronics and done a few basic courses in it .
I hate waste and always try to rescue things and put more life into them.
I'm trying my hand at rescuing TV 's from the land fill at the mo .
Saved a few, not many, but one for my brother was soldering on a replacement LED on one of the strips...Leave a comment:
No activity results to display
Leave a comment: