> Interesting. I've never seen any car where turning the ignition *doesn't* 
> disable all the other electrics in the system [including the headlights].

Try to find a car without just a simple radio, one that does other stuff 
like sat nav etc.  I guess the computer and GPS system etc doesn't respond 
well to being switched on for 2 seconds, the turned off for 1 second while 
the engine starts, then being switched back on again.

> As I understand it, turning the starter motor requires a massive amount of 
> current, and is essentially the *only* reason a car has such a whopping 
> great battery in the first place.

Yup.

> (Certainly it's not necessary just to run the spark plugs... or even the 
> headlights...)

Of course, once your car engine is running you don't need a battery at all, 
that's why racing cars don't have them to save weight.

Post a reply to this message