Material cost is cheaper when using 12v as compared with 6v as current flow is half that of the 6v system and this means there is less voltage drop over a given length of cable arriving at it’s destination, I.e. the headlamp bulb. On a 6v system, this voltage drop can be reduced by using a heavier (and more expensive) cable. Thus when you’re manufacturing thousands/millions of vehicles, there’s quite a material cost savings with 12v
Dave
