The Rodeo is a rear wheel drive vevicle
The four wheel drive light is most Likely staying on when your Isuzu Rodeo is in two wheel drive because of a bad sensor. A licensed auto technician would be able to replace this for you.
Take it to a service shop.
there should be a button on your left of the steering wheel and if not, it doesn't have 4 wheel drive
Put the transmission in the neutral position,then shift the vehicle back in to 2 wheel drive
if it is 2 wheel drive probably 3 hours and if it is 4 wheel drive probably 5 hours
Mine is located on the steering wheel . press the lower portion of the wheel . i have the 1997 holden rodeo .
if you have "on-the-fly" shifting it should go right back into 2wd, get at a lower speed, then try. if not stop the truck put it in neutral shift the gear into 2wd position, if it doesn't go, hold it slightly there and try to put it in reverse. it'll catch the gear.
More than likely you will need a new transmission, a new front axel with differential and a half shaft.
It is on the left side of the engine above the exhaust pipe and not easy to get to. I suggest taking it to a garage/
could be a tie rod
your bst bet is to get to them through the front wheel wells.