Vizio VS420LF1A No picture/backlight

[Blackwolf]

Re: Vizio VS420LF1A No picture/backlight

It says STR w6251 8n06j

[Blackwolf]

Re: Vizio VS420LF1A No picture/backlight

Let me know if you need any other pics, or to know what components are

Thanks again

[budm]

Re: Vizio VS420LF1A No picture/backlight

Ok, I found the spec sheet of the STR, I will have to study it first.

[budm]

Re: Vizio VS420LF1A No picture/backlight

Then I will have to trace out the connections using your pictures, so it will take awhile.

[Blackwolf]

Re: Vizio VS420LF1A No picture/backlight

Any luck? Should i just look into replacing the entire PSU?

[budm]

Re: Vizio VS420LF1A No picture/backlight

Sorry, been real busy, and have been trying to help another person with the same symptom and he is getting the new PS, waiting to see if it fix his problem. Please look and see how much the new board is in the mean time.
Not much luck tracing out all the needed connections yet to see how it works.

[selldoor]

Re: Vizio VS420LF1A No picture/backlight

Please can you do a clear shot of this area have a look at items ringed in yellow
do they look ok/burnt.

[budm]

Re: Vizio VS420LF1A No picture/backlight

OK, I had the time to trace out the VCC for the 12v SMPS IC 201 (I need the P/N of this IC also to verify). Please see PDF. I am sorry that I have to ask a lot of questions and a lot of pictures request, it is not easy to do remote troubleshooting. I hope we will get some where, and may be other people will see something I may have missed.

[budm]

Re: Vizio VS420LF1A No picture/backlight

By the way, this person has PS board that is almost the same as yours.
https://www.badcaps.net/forum/showth...t=19764&page=5

[dmesser100]

Re: Vizio VS420LF1A No picture/backlight

I am also having the same issue with this mode.

[dmesser100]

Re: Vizio VS420LF1A No picture/backlight

I am not getting the 12v feed from the power board to the main board while the vizio is white. get 2volts off the inverter on/off pin. not sure what to start checking next, all caps look ok.