42lg3000-za No Picture but got sound

[Jahson]

Re: 42lg3000-za No Picture but got sound

master
test1=0.00
test2=0.00
test3=0.00
test4=0.00
slave
test5=0.00
test6=0.00
test7=0.00
test8=0.00

And the same results with probes in reverse order.
Have not got to take the cover of t-con as yet, seems a bit tricky. will do tho

[vinceroger69]

Re: 42lg3000-za No Picture but got sound

can you post a pic of the t con and cover we may have some ideas on how they come off.
was the readings taken with the meter set on 20kohms?

[Jahson]

Re: 42lg3000-za No Picture but got sound

ok got the cover of, cable a bit more harder

[Jahson]

Re: 42lg3000-za No Picture but got sound

yea meter was on 20k ohm

[selldoor]

Re: 42lg3000-za No Picture but got sound

Can you see the fuse on the tcon - small white 3A

Think you have tested transformers incorrectly
Put on 2000ohms (Not 20k) and put one probe on pin12 then the other probe onto each of the other 3 pins on that end in turn

[Jahson]

Re: 42lg3000-za No Picture but got sound

meter set to 2k
Master
Transformer T1
test 1 = .000
test 2 = .000
test3 = .000

Transformer T2
test 1 = .000
test 2 =-1 on left side
test 3 = 1 on left side

Slave
transformer T200
test 1 = .000
test 2 = .000
test 3 = .000

tranformer T201
test 1 = .000
test 2 =-1 on left side
test 3 = 1 on left side

[Jahson]

Re: 42lg3000-za No Picture but got sound

Yea fuse on T-con checks as ok

[vinceroger69]

Re: 42lg3000-za No Picture but got sound

i have not tested this type of invertor tranformer myself before i was just going by toms post 65? so not sure but at least you have posted the readings so someone should be able to comfirm for us.

[Jahson]

Re: 42lg3000-za No Picture but got sound

Im really thankful for you guys help, i know its still early, in the diagnostic stages.

[selldoor]

Re: 42lg3000-za No Picture but got sound

Yea fuse on T-con checks as ok

I was hoping it wasnt.

Still dont think we have the correct test for the Transformers. They usually measure 400 -1500 ohms Some of them have one end of the secondary at one end and the other at the opposite end of the transformer. I have looked on line but cant find much on these transformers - but it is good I can read the part numbers in your pics.
The likelyhood of all secondaries being sorted or open is like winning the lottery.

Is there a problem with pics of the backs of the inverter boards

[Jahson]

Re: 42lg3000-za No Picture but got sound

Theres nothing on the backs of inverters , sorry im not at the same place as the TV now.

[Jahson]

Re: 42lg3000-za No Picture but got sound

Aint given up yet, im not at the same place as the tv, be greatful if someone can get me a close up of (vit71053.54 master) just yesday i had a real close look on mines aint sure but theres an area on my board that just dont seems right. Like someone tried soldering or them lil black rectangle bits missing.

I just want compare, my board with a good close up image.

[selldoor]

Re: 42lg3000-za No Picture but got sound

Which area are you talking about - give the board part designations - like Qxxx.
Not all positions are populated - they are just put on the board at design stage in case of need. Its easy to not use a position but difficult to add one later.
We are unlikely to find a picture if you cant - now you see why we ask for good clear pictures?

[Jahson]

Re: 42lg3000-za No Picture but got sound

selldoor you see the pix in post#86

If you look in the center of board, it looks like bits of solder all over the gaff.
I know whot you saying but this looks kinda unprofessional.

[budm]

Re: 42lg3000-za No Picture but got sound

Post #6
"pin 1 is a blue wire should be 24v
pin 2 is grey 24v
pin 3 is grey 24v
pin 4 is grey 24v
pin 5 is grey 24v

Then the next 6 to 10 are GND
pin 11 =BR1
pin 12 =on/off
pin 13 =pwd dim
pin 14 =error"

So do you get 2.9VDC (as indicated in post11) at the pin 12,
Pin 14?
By the way, what is the P/N of the Inverter controller IC?

[Jahson]

Re: 42lg3000-za No Picture but got sound

Budm
post #11
pin 10 on/off meter reads 2.9
pin 11 pwm dim meter reads 0
pin 12 n.c meter reads 0

[selldoor]

Re: 42lg3000-za No Picture but got sound

selldoor you see the pix in post#86

If you look in the center of board, it looks like bits of solder all over the gaff.
I know whot you saying but this looks kinda unprofessional.

Ones I have looked at are just the same

Here is one example
http://flattvparts.co.uk index.php?main_page=product_info&products_id=7884

- google the board number and you can find others

[budm]

Re: 42lg3000-za No Picture but got sound

Please see the redlined test points with reference to the chassis ground.

[budm]

Re: 42lg3000-za No Picture but got sound

By the way, do you see this?
http://www.ohmsupplies.co.uk/REPAIR-...T7105354-LG-42

[budm]

Re: 42lg3000-za No Picture but got sound

Oops: duplicate