vizio gv42l dead please help

[budm]

Re: vizio gv42l dead please help

So I tried to ground the base of the Q3 and it turned the U1 on and eventually powered up the other ICs. So this part appears to be working as designed.
It did not turn on the PS-ON though.
Any ideas?

The same micro controller that sends out (directly or indirectly) the PS-ON is more likely to be the same one that send the signal to turn on U1.

[zape]

Re: vizio gv42l dead please help

Guess what was is.
"Power on" switch button on the side of the TV.
It did not survive humid climate of Florida and just rusted.
Lesson learned. Check simple things first before going to traces and drawing diagrams.

[jetadm123]

Re: vizio gv42l dead please help

Good work! Sure beats buying a main board!

[budm]

Re: vizio gv42l dead please help

Guess what was is.
"Power on" switch button on the side of the TV.
It did not survive humid climate of Florida and just rusted.
Lesson learned. Check simple things first before going to traces and drawing diagrams.

Good find, at least now you know what the PS-ON is for, how to test the Voltage regulators, how the Half-Bridge transformer drive function, how to force on the P-CH MOSFET, etc.

[budm]

Re: vizio gv42l dead please help

Good work! Sure beats buying a main board!

Beats getting a new transformer too for the power supply or the whole power supply board..