HPDV5T-1200CTO notebook, just replaced hinges, now it won't power on

Question

 I will go ahead and shoot my question and maybe one of you guys can give me a hand. I have an HP DV5T-1200CTO notebook. The hinges snapped along with the plastic piece that covers the inverter, that snaps in. All the snaps broke off of the screw that hold it in. So after getting a new hinge and makeing a new plastic piece (to order one they wanted $120.00 for a new one, ya right like I was paying that for a small piece of plastic) I very carefully removed the battery, held down the power button for almost a minture to drain all the power from the system, took out the hard drive, ram, and CMOS battery.
I've repaired hundreds of laptops and when working deep into any laptop always take out the cmos and drain the power to prevent any shock to stuff. So after taking out all the screws, popped the plastic pieces edges, gentrly unplugged all the connectors as usual (it had those weird no clamp, you just pull or push ribbon connectors for the power button and 1 other connector had that weird just push or pull zip connector, the rest weire normal flip the latch ribbons connectors. Anyways, after I got the LCD apart, I swapped out the old hinge for the new one and gently put everything back in its place along with my new plastic inverter cover piece. When I was completely done and put the cmos in and everything else was together, I plugged in the HPDV5T-1200CTO and the charger port / plug lit right up. But when I push the power button nothing happens! NOthing! So i took out the battery and tried it a bunch of different ways but nothing happens. The battery light comes on and stays blue for about 30 seconds to a minute and then goes outl.
What in the world could have happened? It's like pressing the power button doens't power it on. The power input ring lights up and stays lit no problem and the charger light comes on and stays on for 30 seconds or a minute then goes off. I know I didn't miss or break anything. Every screw and connection went right back into the same spot it was before the hinge replacement and all I took out were the screws to get to the hinges and carefully using nylon covered tweezers undid the zif connectors to remove the power button board and keyboard. I'm baffled because it powered up and worked fine even with the screen floppping because the hinges were snapped. If anyone has any idea of what it could be, please let me know. This is a really nice notebook with very low hours. I even have a 240GB solid state hard drive for it, so I don't want to junk the notebook. It's from 2010 but I've replaced way harder things on tons of other laptops and they fire up after the repairs. Thsi is the first time I've dealt with those stupid "No clip" ZiF connections on any laptop though. Could the power button be bad? The way it acts, is as if the pwer button is broke. Hopefully someone has some ideas.
Thanks!

Answer 1

Remove the main battery. Leave the AC adapter connected with the machine shut down for five or six hours to recharge the internal backup battery. Then try starting it up on AC power.
If that works, leave the AC connected until you have a new main battery in place and charged up. The backup battery will drain completely in a very short time if you disconnect the AC without a good main battery in place, and you'll be back in the same situation again.
If the machine still won't start after 5-6 hours of recharging the backup battery, reset the PRAM, then try again. If that doesn't work, you'll need to replace the backup battery too.