I would check all of the connections on the alternator and the battery to be
sure you don't have a loose connection.  The alternator should be charging at
above 13 volts (13.65 on my van).  If it isn't then it could be tired.  Also
check your alternator belt for looseness as this could be slipping at speed
and causing a problem (happened to a friend of mine recently).  Hope this
helps.

Thanks,
Ken Wilford
http://www.vanagain.com
John 3:16
Phone: (856)-765-1583
Shop:   (856)-327-0027
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