Lenovo Ideapad Z-710 no power leds after rewiring faulty power cable

[Bill MacIntyre]

I am hoping someone can help me troubleshoot my Z710 as it is my main Laptop and badly needed.
I am hoping for troubleshooting tips or a schematic to help to troubleshoot the mobo.
Lenovo forum and phone support were of no help.
Lenovo would not give me a service manual and only sent me links to useless videos on how to dismantle and re-assemble it.
The power jack (rectangular) was acting up for a long time due to wear and eventually wires popped off the jack. I re-soldered it and it worked for a week then all of a sudden it would not power up.

I removed/re-inserted the power plug a few times and the power LED seemed to light for a second I could not get any sign of life at all.
I took it apart (again) and cut the power cord and soldered it directly to the cable inside
There are 5 wires on the cable, 2 black, 2 red and 1 blue but looking at the jack and the mobo, theres only actually + and minus connections. On Mobo power connector, 3 pins to + and 2 to -
Both blacks are tied together and 2 reds and blue tied together (+)
So now I have + going to Red+Red+Blue and Gnd going to Black+Black
I see 19 volts at the power connector on the motherboard but pressing the power button does nothing and no LEDS light up. Tried with and without battery (I believe bat is dead)

Does anyone have any tips?
Maybe something simple like needing to hold the power btn down for 30 secs. or something… (tried that)
If not where can I find a schematic to start some board level troubleshooting
I have an Electronics background
Any help really appreciated. I need this working asap

 

[Lutfij]

1| When you align the adapter to the notches on your laptop's backplane, you should take note of the wires colors as they plug in.
2| Did you follow this guide during disassembly?
3| I wouldn't advise in directly hard wiring your laptop to run off the mains since it can and will damage your components. The battery should be replaced and perhaps given to a certified technician. I'm not doubting your electrical skills but asking what you asked may be a sign that this is a little over your head.