Knew a bloke with a Jag, electrics by Lucas, that had head lights, indicators, brake light, power windows go out on one side of his car after an electrical storm before just as mysteriously starting to work again a couple of days later before the other side went then everything all together. Prince / Lord of Darkness was a running joke for ages every time he was late for work with another car drama story, though half the time or more I suspect he slept in and was just blaming the car.
As for drivers sleeping, if you weren't driving or servicing the vehicle (or any of the multitude of other jobs they had you do), sleeping in your seat was perfectly sensible thing to do, even in a seat as uncomfortable as the M-113 one I used to inhabit as a lowly driver.