Your alternator may be bad.  You might as well get it checked for fee at
an Autozone/Advanced Auto.  But, you should also check and fix your
grounds, even if the alternator is bad.  The three I'd check are the
battery ground, the engine compartment ground (from the middle to the
left side of the engine compartment), and the ground strap from the
front of the transmission to the frame.  Take them off, clean the
contacts, and if they look old, replace them.  Might as well change them
all, just for good measure, if you ask me.

When you get the alternator checked, make sure they check the battery too.

Good luck,
Wes

wogdog wrote:
> I got a reading of 12.6v
>
> */Wesley Pegden <wes@cs.uchicago.edu>/* wrote:
>
>     I would check your voltage across the battery when the car is
>     running.
>     Hopefully up near 14v, at least 13.5.
>
>     -Wes
>
>
>
>     wogdog wrote:
>     > Volks,
>     > After a long uphill climb into a head wind and in 3rd gear I
>     noticed that two lights had come on at the instrument cluster. The
>     O2 sensor and the charging system light, the one with the battery
>     next to it. Tried resetting the O2 sensor but no luck there. Do
>     you think it could be a grounding problem? The van seems to be
>     running just fine but I don't like the thought of driving it with
>     those lights on. Any insights or tests to run would be greatly
>     appreciated. I do have a multi meter but I'm not to good at
>     electrical diagnostics
>     > Thanks,
>     > Paul Rogers
>     > 85 Westy Weekender
>     >
>     >
>
>