Atari Lynx II Power Diagnosis?

[Ghudda]

So I gambled and decided to pick up a CIB Atari Lynx II that was listed as for parts. It's simply not powering up with either the official power adapter (DC 9v 1A) or batteries. I get nothing. I opened it up and checked capacitors and I can't find any blown fuses, etc. Any particular points on the board I should be checking for damage? Also, I hear the MOSFET transistor at Q12, which has to do with powering on the system can go bad and need replacing. I did run a wire from the headphone jack to the negative battery terminal and it still won't power on.

EDIT: I have a wire soldered from the headphone ground to the terminal and when I plug the power supply in, the screen will flash on and then immediately off. But it does seem to power on fine with batteries. Should I replace the MOSFET?

EDIT2: When I power it on via batteries, I just get a blank screen (backlight does light up). No sound/game picture, etc.

Anyone experienced with Lynx II repairs and have some ideas for me to try?

[Exhuminator]

Well, I've read that a Lynx II won't power on unless it has a cart in it.

[Ghudda]

Well, I've read that a Lynx II won't power on unless it has a cart in it.

I think that's correct. I am testing it with a cartridge inserted.

[Exhuminator]

If that doesn't work, maybe this thread can help:

https://atariage.com/forums/topic/10140 ... apacitors/

Sounds like the Lynx II is a fickle beast.

[Ghudda]

If that doesn't work, maybe this thread can help:

https://atariage.com/forums/topic/10140 ... apacitors/

Sounds like the Lynx II is a fickle beast.

Yeah, that does seem to be the case unfortunately. AtariAge may be my best bet.