The emergency power supply has been activated. And now, the ship is humming with life once more. You have fought hard and now you're nearly there, within the Source Antechamber, but it's not over yet.
You start beyond the large doors from the Emergency Power Supply, in the Source Antechamber corridor. Power is back on.
Go up the corridor to the crossroads ahead, and look at the exits. A lift ahead is barred off. There are doors to either side, so take the one on the left. Watch out for the SkaarjLord who may greet you here.
Go round the corridor behind the doors. Half way round you will find a button - but it won't operate until you have killed the Skaarj. If you haven't met the Skaarj yet, then go on round the corridor and find it. Kill it then operate the button.
Return to the crossroads once the button has been pressed and approach the bars over the lift - they spring open. Step aboard the lift and ride it to the top. In the room beyond, a force field bridge lies ahead and there are alcoves to either side. Go to the alcoves (hatches open inside as you approach) for gear including an Assault Vest, a box of 8 Rifle Rounds, an ASMD Core, a box of Razor Blades, a box of 50 Bullets and a box of 10 Flak Shells.
Leave the alcoves and approach the forcefield bridge. Go across it towards the platform with a hole at the end - you will be sucked down through the hole and on through a hatch in the floor, before tumbling down a very long tunnel. When you reach the bottom, the level changes.