insignia NS-L47Q09-10A no sound or picture

[jose6326]

How are you doing guys? Im back
I have missed this site I have been so busy at work havent had time to fix the tvs I have
But now I do have time


Anyways I picked this tv up for 20 bucks
The guys siad he was watching it and it just went black

When I power it on I only here the main board on (humming noise)
The led light does not even come on and I do not hear any noise from the psu or tcon like most flat screens do

When I pressh the power button I get nothing

There are no visible faulty components

I read on another post that the problem with these tvs is that the inverter board goes bad
I tested the fuses and they are good

I did some testing but I will post after this

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

in the picture I uploaded I tested the voltages

I am getting 24v to the inverter board


on the PSU I am getting the labeled voltages by the connector

12v
24v
5v

for on/off I am not getting any reading even when I press the on/off button
"DIM" I am not getting any reading

I will post a picture of the labeled voltages tonight when I get out of work


any suggestions on what to test next?

[budm]

Re: insignia NS-L47Q09-10A no sound or picture

"for on/off I am not getting any reading even when I press the on/off button
"DIM" I am not getting any reading" That means the main board is not sending the ON/OFF (BL_ON or INV_ON) to turn on the inverter circuit, also no dimming signal either.
PS_ON is OK from the main board otherwise you will not have the 24VDC or 12VDC.
So main board will have to be looked at next, I would check all the fuses if any on the main board, then the voltage of the regulator ICs.

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

I don't remember seeing any fuses on the main board
but I will check again when I get home

I need a refresher course on how to check the ICs again


thanks bud

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

Here is a pic of the connector I tested

On/off - no voltage reading when button pressed
Dim- 0.005
12v - 11.59
12v- 11.59
24v- 24.55
24v- 24.55
Ps_on- 1.060
5v- 4.98
5v- 4.98

[budm]

Re: insignia NS-L47Q09-10A no sound or picture

The main board is not sending the Inverter ON or the Dim signal. You should remove the main board to good visual inspection to see if any components are damaged and do the voltage test..

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

Bud I pulled the main board and inspected it with a flash light for 10 minutes

I didn't see any visible damage or any fuses to check either

I will visually check it again

How do I do the voltage test?

[budm]

Re: insignia NS-L47Q09-10A no sound or picture

Hers is the link which also under my signage.
https://www.badcaps.net/forum/showth...999#post300999

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

Ok I tested the voltage regulators on the main board

Hopefully I did it correctly from the link you provided


#1 L222
Pin 1- 0.000
Pin 2 - 0.921
Pin 3- 0.978

#2 1084
Pin 1- 0.000
Pin 2- 0.093
Pin 3- 0.396

#3 L192
Pin 1-7.02
Pin 2- 8.26
Pin 3- 11.58

#4 AZ1117D
Pin 1- 0.000
Pin 2- 5.02
Pin 3- 8.26

I provided 2 pics hopefully they are clear enough if not I can take more

Thanks for the help and happy fathers day

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

i also used freeze spray by turning the can of compressed air upside down

but that had no effect on the tv operation

[budm]

Re: insignia NS-L47Q09-10A no sound or picture

"#1 L222
Pin 1- 0.000
Pin 2 - 0.921
Pin 3- 0.978

#2 1084
Pin 1- 0.000
Pin 2- 0.093
Pin 3- 0.396"

Those two regulators (if they are regultor ICs) are not getting enough input voltage to operate, without the diagram to find out where the voltage source for these two regulators are from it will not be easy. Can we get the full numbers as printed on the bodies?

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

I will get the numbers for you today when I get home from work


thanks

[budm]

Re: insignia NS-L47Q09-10A no sound or picture

OK, this may work, the NS-L42Q-10A main board looks almost the same as yours (http://www.shopjimmy.com/insignia-cb...s-l42q-10a.htm)
Here is the service manual for the NS-L42Q-10A:

You can download and see if it is close enough to your board.

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

Here are the numbers

#1
L222
G1084-33

#2
1084
-18PE
956E7R

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

I downloadwd the file from the link you provided but its telling me it cant be opened because its not a valid pdf file

[budm]

Re: insignia NS-L47Q09-10A no sound or picture

Here are the numbers

#1
L222
G1084-33

#2
1084
-18PE
956E7R

OK they are 3.3V and 1.8V regulators.

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

So are they defective?

[budm]

Re: insignia NS-L47Q09-10A no sound or picture

NO, they are not getting enough voltage for them to work.

[budm]

Re: insignia NS-L47Q09-10A no sound or picture

OK, I look at PDF page 69, please check the voltages on these regulators:
U701, 702, 703, 705, 709.
Those 4 regulators that you report the reading, what are their designator, U????

[jose6326]

Re: insignia NS-L47Q09-10A no sound or picture

#1 - u703
#2 - u702
#3 - u708
#4- u709