Vitara just stopped

U need to check any gas is coming out from injectors or no,spark at the spark plugs,or it might hv timing belt broken,have many reason won't start.u need to know mechanic work to diag

i had the exact same thing happen to me with my first car, a 1966 mercury comet.

i replaced the fuel pump, rebuilt the carburetor (twice), and finally rebuilt the entire engine! still, every time afterwards, the car ran ok, then would cut off again!

it turned to be just a $2 clogged fuel filter. i' suspect the same with your vehicle. after removing the filter, simply blow through it. any resistance, means it needs replacing.

Follow cable to transmission to see if it is loose.

Something siezed up like a drive for the oil pump ,just call the scrapyard and buy another car it will be cheaper in the long run

If the engine cranks but won't start, the battery and starter are out of the picture.
When it won't start, someone will need to check fuel pressure and for spark at the plugs to proceed.

Sort of sounds like the timing belt broke-- if you have one

The valves may have hit the pistons & that is why it won't turn over

I don't know any of that is true & won't wish it on anyone,but
it is a place to start

Check the electronics,cam sensor or crank sensor these are the culprits.

Could be the cranking amps in the battery are under par. Needing new battery. Or the alternater is not working properly.

Check /replace thermostat

Does your model have a "lock" function for the centre differential when in 4WD? I would guess you have it in "lock" and this means that one end of the car HAS to slip to maintain the same travelled distance by each end of the car. Try driving it in "open" or "auto" maybe. The other thing that could be making things interesting is ESP if it is fitted and active. I have no experience driving on ice, but I can imagine it being similar to some of our gravel roads in Australia.