insignia NS-L47Q09-10A no sound or picture

[jose6326]

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

I can not find U702 or U705
I looked for 10 minutes on both sides of the board and I cannot find it

[jose6326]

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

hey budm I was trying to trouble shoot the problem from page 54

but the components it tells me to test are not on the psu, main or tcon boards


Im not sure if this service manual is for my tv

[budm]

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

That is why I have you look for those IC's to find out if the service manual will be close enough to use to troubleshoot your board. Without diagram it will be real hard to trace that complex board to find out what is going on.

[jose6326]

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

Is there anything else I can test?
I can take pics of each component

[jose6326]

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

I looked at the main board that is pictured in the service manual you provided and it looks exactly the same as mine

I will look again maybe I missed something

[jose6326]

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

you think I should take a chance and just buy the main board?

[budm]

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

Yes, just make sure it matches your original board and verify that it can be returned if it is not the right one.

[jose6326]

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

Budm I was looking at page 60 in the service manual you provided

I matched every component to the my board and to the board on page 60 and it is exactly the same

The only difference is the part number

My board is 715G3269-1
The board on page 60 is 715G3269-G

Like I said before every component is the same and labeled the same as well

Also when I went on ebay searching for my board the same exact board comes up and the model number of the insignia tv from the service manual comes up
So im guessing this board is the same for my tv and these other 2 models

[Agent24]

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

Same board but different version\revision. You have -1 revision, manual shows -G revision.

There will be a difference somewhere, which may or may not matter.

[jose6326]

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

Same board but different version\revision. You have -1 revision, manual shows -G revision.

There will be a difference somewhere, which may or may not matter.

but I didn't see any difference
I spent 45minutes to an hour matching every component on my board to the one in the service manual

everything is the same

now I just need help testing it before I buy another on from ebay

[Agent24]

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

Might even be just a minor board layout change or some other subtle thing. Likely it won't make a difference.

[jose6326]

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

so any suggestions on what else to test?

[jose6326]

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

https://www.badcaps.net/forum/showth...light=insignia

just posting this here so I don't have to search for it

[Agent24]

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

so any suggestions on what else to test?

You need to find out why U702 and U703 aren't getting any power. Can you trace their input pins back to another component that might be locatable on the schematic?

[jose6326]

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?

#1 is U703
#2 is U702

[Agent24]

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

Yes, they are getting some power but not enough. A standard linear regulator can't supply more voltage than what comes in. Only less.

I've attached datasheets for U703 and U702. Check to make sure you measure the right pins too.

[jose6326]

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

I checked the correct pins

Pin 1 is ground
Pin 2 is v-out
Pin 3 is v-in
I get the same readings as above

[Agent24]

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

You will need to trace back their inputs and find where their supply comes from.

Going by the photos, U703 gets its input from the output of U706 via L705. If that is the case, what is the status of U706? Does it have power?

I have attached its datasheet too.

EDIT: Sorry, I confused myself. According to the schematic and block diagram, U702 is powered from the output of U706. U703 is powered from the same rail (+5vSB) that also powers U706.

If U703 has no power, then U706 won't either, which is why U702 isn't getting any.

Looks like you need to find out why that +5vSB rail is low. Maybe there is a short somewhere? You say you get +5v from the PSU. Is that with the mainboard connected or not? Do you also get +5v at the mainboard?

[jose6326]

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

Yes I get +5v with the main board connectedi tested the connector on the main board coming from the psu and I am getting+5v

[Agent24]

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

You get +5v on the mainboard connector, but does the +5v rail get to pin 1, 4 and 7 on U706?

Looking at page 81, U706 gets +5v (via +5VSB) before the other regulators - the other regulators have their +5v (VCC5D) switched through Q703.

You should also check that the +5VSB is getting to all the components in Q703's control circuit.