Turian Ark: Lost but Not Forgotten
Locations: Elaaden, Remav System
The quest for the Turian Ark picks up again once you have access to Elaaden- there's a strange signal there which may point to the ark. Follow your navpoint to the far north east to discover a number of abandoned cryo-pods being scavenged by raiders.
Take out the raiders, then scan each of the pods in turn to reveal that the Pathfinder, Macen, isn't in any of them.
There's a pod that still has energy- opening it triggers a brief cutscene that ends with a minor AVP bonus. Scan any remaining pods for a new obective back on the Tempest.
Place a vidcall to Avitus, and learn that he's got a fix on the location of the Natanus, probably.
Follow his visions to a navpoint in the Remav system.
Board the Ark, but don't fret too much over your loadout- there's no fighting in this part of the mission. Loot the container you can spot in the opening conversation, then scan the big door up the stairs.
There's a terminal down the stairs you can read for some emails, but use the Ark Natanus Console by the south door to open the way forward.
You'll be seeing this power-diversion thing a lot in this mission. Scan and loot the next room- use the console to open a door and spark a brief discussion about you and SAM. In the next area, open the left door before diverting power- the wreckage behind it can be scanned for data.
The diversion console here is actual in the previous room, so drop back and activate it before heading through the right door.
Continue on to the SAM Node (the diversion panel is at the east end of the hall). The big choice of the quest is whether to persuade Avitus to take up the Pathfinder mantle, or let him off the hook. Unless you're just a fan of misery in general, give him the boost of confidence he needs to become Pathfinder. If you don't, the turians remain Pathfinderless for the rest of the game, impacting the final fight, making it impossible to save Captain Dunn's life later on, and leaving Avitus himself a drunken wreck on Kadara.
Finishing this conversation returns you to the Tempest with mission completion.