Let’s assume that good old ulf has the presence of mind to keep his various housecarls and serfs from making off with the shiny bits and using the remaining bits of car as a hencoop or privy and was able to keep the parish priest from burning it as a tool of the devil. Suppose they put their top men on it – which would probably be the local blacksmith and a couple of bright monks maybe trained in logic at the Irish monastic schools.
I think they’d instantly identify it as some form of wagon or chariot. It’s got four wheels and a bunch of empty space. But it’s all made of shiny, shiny metal and a king’s ransom’s worth of the finest glass they’ve ever seen. Also, there’s no obvious place to hitch a horse and the damn thing weighs more than any cart you’ve ever seen. So maybe it’s a king’s chariot or burial artifact?
Step 1: Can they get the doors open? Almost certainly yes. Then, after they spend some time cowering in the privy after seeing the lights come on, they might be able to do some more reasoning. The seats are going to look like the seats of a wagon or a cart. The wheel – well, ship’s wheels are still 600 years in the future, and until the key is turned, it won’t turn. So the concept of a driver’s seat may not be obvious except from the cart analogy. Will they figure out that wheel == reins?
On the other hand, the key is in the ignition, and keys have been around a while. So if this was an automatic, then they’d be mostly there once they figure out how to turn it.
Given that this is a standard transmission – this might be as far as they get. The pedals would be a problem. 300 years later, and maybe an organist might figure out, by analogy, that pressing pedals in different patterns makes the car behave differently.
So yeah, I think what’s going to happen is that they’ll figure out it’s a chariot; they may deduce that it’s supposed to be self-propelled, but there’s damn all chance that they’ll figure out how to use it without destroying the starter and the transmission.
I could see them accidentally roll starting it. If it’s parked on a hill, and they have the key turned to the on position to admire the glorious light display on the dash, they might try stepping on the clutch and then panickedly let it out when the truck starts rolling and then… vrooom. At which point I’d imagine they’d run it into the nearest tree, but maybe if they got lucky they could figure out that the middle pedal stops it.
Another thing is that unless the “no directions” means Mr. Kobayashi erased every single piece of text out of the car, there’s probably still enough text that they could get some hints if they methodically studied it. It’d probably be even easier a few years later after the Norman Invasion, but they could probably figure out most of the words if they spoke Old English and Latin, albeit not their meaning in the context of driving a car.
For one thing, this is a manual transfer case 4x4 so it has a plate somewhere with a short novel on how to operate the transfer case. That won’t precisely tell them how to drive, but it could give the general gist of using the controls to move the truck. Also, as soon as they do turn the key, the magic-looking LCD display will say something like “depress clutch to start.” I doubt they’ll get “clutch” but they might get depress and start which might give them the hint to try the pedals in combination with other things.
I doubt that even the few people who were literate could understand many of the words in a manual, so that would not be much help anyway. I remember reading that in WWII natives on South Sea islands would be tooling around in army trucks in a matter of a few weeks. Doesn’t fit your specifications, but it shows that quick learning is possible, jumping from stone age culture to modern, with a few cues.
But again, going in reverse. Unless one has studied the arts and crafts of that age a modern person would also be very lost doing some things from that era. For example making a sword out of a hunk of raw metal.
Send it back 600 years, when someone will be around to read a North American owner’s manual written in modern English, French, and Spanish, and they might have a fighting chance.
Medieval European societies had complex rigged sailing vessels. Give a car to a fairly educated person from 1400 – a merchant, monk, university professor, or whatever – and they’ll figure it out. If the car is tuned to use pure alcohol as a fuel, they understand the concept and importance of an alcohol-water mixture as antifreeze, and the engine is filled with synthetic oil, they’ve got a fighting chance at keeping it running for about 10,000 miles. Then again, you’re talking about a Land Rover, so let’s say 2,000 to 3,000 miles.
I’m not sure that figuring out how to use it would do them much good unless, as elmwood says, it’s been modified to use alchohol. Even then, how do you keep the tires full of air?
They might be better off sticking it in a king’s or lord’s garden and using it to have private conversations. Nice greenhouse effect in the winter.
They wouldn’t need one that’s modified for alcohol. If you send one back with a diesel engine, I’m sure they could figure out how to make biofuels out of vegetable oil or animal fat.