Mark, I have found this problem, normally, to be that the sliding door has
moved a little over time and the contacts for the power locks are not lining
up any more.  Here is what I normally do to see if this is the problem.  Shut
the sliding door and hold an upward pressure on the sliding door handle while
locking the front door on the passenger side with the key.  Most of the time
this will allow the pins to line up and your sliding door lock will work
again.  Now you just need to loosen the allen head bolts at the bottom of the
door and adjust it up a millimeter or two.  This should fix your problem.

Hope this helps,
Ken Wilford
http://www.vanagain.com
John 3:16

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