The problem is with your alternator.  Probably worn brushes.

The way the vanagon is wired, you'll get both lights whenever the alternator
isn't putting out properly.

Mike

> When I drive over 4200 RPM my batt & OXS lights used to  flash (last week)
> now they come on & stay on over 4200 RPM
>
> Does anyone know what it is & should I get it to a fixer,  or can I fix it
> myself without a diagnostic computer.
>
> Sam W
> 63 singlecab
> 70 Westy
> 87 vanagon auto/AC Westy