If and when you do make a mistake in your Owner's Manual, you will most likely die in a horrible, reckless way. However, in nearly all of these cases, you will be presented with a free ride to the Diesel County Morgue:
You Are Dead.
Better luck next time.
Since you're dead at this point, the only way to start over is to read the Diesel County Coroner's report of your death. In that, you'll see every gruesome little detail of what you just did that finally ended your chances of making it out alive.