Couple of (stupid) questions

Didn't have time to play as much as I would have liked this weekend, so I still got few open questions:

I've only got the runner, so here's two about cars:

1) Can you take passengers to cars?
2) If yes, can the passengers do anything while you drive (use turrets or shoot out the windows)?

And about ark salvage

3) So far only use for ark salvage I've found is to buy keycodes, is there any other uses for it?

Since we're talking about keycodes here

4) Where can I get key fragments?

I think that's about all for now.

1) Yes but I believe they have to be in your group.
2) It depends on the vehicle but with most, I think that the passenger can just sit there and give stern glares.

As for 3 and 4.... I really don't know. Sorry.

In open world passengers have to be in your group and can only ride along for now. But the Cerberus vehicles found in some co-op missions and PvP missions have a rear gunners seat with a machine gun, and a passenger seat who controls a rocket launcher but those vehicles arent available for players to own.

The Gulanite Crystals are also used to add mod slots to weapons

Keycodes are rewarded for Arkfalls and the roadside events you find all over the game