What does a Terminator do after its mission is accomplished?

Question

A Terminator is essentially given a mission or an objective ("Go back in time and kill Sarah Connor" or something of the like).

What does a Terminator do once its mission is accomplished?

We see in Terminator 2: Judgment Day (the live-action movie) that the T-800 (played by Arnold Terminator Schwarzenegger) completed its mission of protecting the Connors, and then sort-of just melted itself into nothingness (presumably to protect the world from discovering Terminators again).

But what would the T-1000 or the T-X (in Terminator 3) have done?

Are they given multiple directives ("Go kill Sarah Connor, then go kill Robert Baratheon, and then have a nice hot bath; you've earned it")?

This question is related, but not a dupe: What were the Terminator's instructions following termination of Sarah Connor?

Answer 1

Terminator

The original script treatment makes it clear that the Terminator did have a way of telling whether it had got the right Sarah Connor. It was checking for a distinctive leg injury she'd suffered prior to Judgment day. The irony is, of course that she suffered that injury while fighting the Terminator:

Vukovick stops the report. Did he hear correctly? Two homicides in one day with the same name?

"That's not all that's the same," Buckman says, lifting one of the girl's pant-legs which has been slit up past the knee. Also slit, from ankle to knee, is the skin and muscle of her calf, peeled back like a hotdog bun to expose the shin-bone.

Vukovick scowls. The same mutilation as the Encino housewife, left leg only. Too fucking weird. The news guys'll have a field day with this... the first one-day pattern killer.

Since we know that the Terminator has a "win condition" and cannot self-terminate, this gives us two possible options for what it would do after; proceed to any secondary targets or simply hibernate.

T2: Judgment Day

In the novelisation for Terminator 2, we're explicitly told that the termination of Sarah Connor is a secondary target, even after the death of John Connor.

At the Voight house, in John’s bedroom, the T-1000 was reading the last of the letters from Sarah. It scanned the return address on the envelope, PNT-82, ISOLATION WARD, PESCADERO STATE HOSPITAL, and the date, (only two weeks ago), and quickly concluded that the primary target may go there. In a matter of moments it was moving down the street, away from the city, and toward its secondary target.

Terminator 3: Rise of the Machines

In Terminator 3, we see that the T-X has a list of "secondary targets"; known accomplices of John Connor who would become his key lieutenants in the fight against Skynet. In the absence of a primary target, she begins killing the secondary targets. It's reasonable to assume that the Terminator would also have some tertiary targets, perhaps known rebel strongholds or senior commanders that it would attempt to terminate.

Terminator: The Sarah Connor Chronicles

In the episodes "Heavy Metal" and "Self Made Man" we see a Terminator place itself into a low power hibernation-mode in order to avoid polluting the timeline. Given the evident restriction on 'self-termination', it's possible that the Terminator would just hide itself until it could make itself available to Skynet.

Answer 2

• T-800 from T1 didn't have any way to identify Sarah Connor (as witnessed by killing two wrong ones first), so its mission could never really be accomplished. It would have to stick around forever, ensuring that no OTHER Sarah Connors popped up. That's what happens when you let amateurs write software specifications.

• T-1000 in T2 didn't ever discuss the exact parameters of its mission, we only know that it had to eliminate John Connor. Logically speaking, if I was Skynet and was to program a Terminator and it had nothing else to do, I would have told it to go low to the ground and await Judgment day, that way I get a free T-1000 advanced unit to use.

Since I refuse to acknowledge the existence of more than two movies, that concludes the analysis.

Answer 3

There's an answer in The Sarah Connor Chronicles episode "Heavy Metal". Skynet despatches a T-888 to the past to secure a warehouse of coltan (the alloy Terminator endoskeletons are built from). Having done so, the T-888 shifts into standby mode, to guard the warehouse and wait for the future to arrive.

Dialogue from the episode suggests this is standard behaviour (or at least, it's not surprising behaviour):

Cameron: ... He completed his mission. He powered down to standby mode until he's moved or triggered awake.

So from there it seems logical to speculate that the standard protocol is to power down to standby, and wait to be woken up by Skynet in the future.

Answer 4

In Terminator 2, the T-800 mentions that both it and the T-1000 have "detailed files" on significant individuals, and are capable of some flexibility to defend Skynet and damage the resistance. In relation to

Sarah's plan to kill Miles Dyson

the T-800 tells John:

This is tactically dangerous. The T-1000 has the same files I do. It knows what I know. It may anticipate this move.

Skynet is nothing if not efficient, and having made the massive investment of resources to send Terminators back through time, it would want to get the greatest possible return. So they would be programmed to strike for maximum effect. This might mean attacking secondary targets, or going dormant until after Judgment Day, depending on the circumstances.

If we are willing to consider Terminator 3, it provides some additional evidence for this possibility. The T-X had a list of secondary targets in addition to John Connor:

It kills several young people who would otherwise grow up to be leaders of the resistance.

If it succeeded in terminating John Connor

and Katherine Brewster

we can assume it would move on to a tertiary list of targets. These might be other named individuals, or perhaps structures such as

the bunker where John and Katherine take shelter from Judgment Day.

Answer 5

Two earlier answers (PhilPursglove's and Valorum's) mention a Sarah Connor Chronicles episode hinting at the Terminator going into "sleep mode" when its mission is completed.

The latest movie in the franchise, Terminator: Dark Fate, offers a slightly different option, where the Terminator still awaits further orders, but does so while continuing to infiltrate in human society. Consider the following line, when the T-800 explains what happened to him after Judgment Day was prevented by the Connors:

CARL: When my mission was completed, there were no further orders. So for 20 years, I kept learning how to become more human.