Replacement battery won't charge & won't boot with MagSafe/no battery

Recently serviced my machine: replaced cracked screen, swollen battery & reflowed solder on graphics chip (computer kept rebooting during use). When I reassembled, new battery was almost at full charge & everything seemed to be working normally (no involuntary reboots). When I ran charge down to 5% I connected MagSafe charger but no orange or green light & battery not showing charging in toolbar. Computer is now dead, neither MagSafe chargers will charge computer or have orange/green light, but both chargers work normally with the other MacBook Pro. I was using the computer without the battery for a few weeks before I replaced it, but now that won't work either.

Any ideas?