Atari Lynx Repair

So I've taken it apart and cleaned and I've recapped it fully, and replaced the MOSFET but still no power.

I then tried the power trick with the wire from battery -ive to the headphone jack +ive. The screen lights up but that's it (even with a game inserted).

I had lightly soldered the wire to the headphone +ive and it fell off, so I tried it again just to see for sure if anything was on the screen and it actually turned on once and the game started (so it's not totally dead)

Here's the strange bit: when it played I took the wire away to cut out the bypass and it stayed playing. I've tried it a few times more but the game won't start again, however, it seems I can turn on the Lynx and it lights the screen if I just touch the wire to the headphone +ive and then remove - it does not need to have a constant connection.

I then had a look at the flex / membrane circuit and some of the traces are broken - I've tried to fix it with conductive paint but no joy yet.

How do I power the lyny on without the membrane connected ?
This is the Schematic from Console 5

Specifically this bit:

Do I join Power On and +5v, pr is it Power On + Power Com ? Or something else ?

I want to figure if the issue is the membrane or something more....

Yep - I did but wasn't getting an answer, but I did this morning