As I mentioned, I've never used the "remote fob." It has never left the
key hook in the house. And since this happens not only at home, but all
over town....

I will look into some of the electrical issues mentioned here.  Nissan
does have TWO TSBs out on this, although my local dealer denies
it....Maybe I'll break down and pay the $20 "access fee" to the TSBs
that Nissan or Alldata demands and see what they have to say....

My 1997 Nissan Quest has starting -- intermittently -- locking the
doors on it's own.

I'll walk away from the unlocked van and come back later and sometimes
it will have locked itself up. Sometimes all doors, sometimes only a
couple.

I live in the remote woods, no one else around. I've never used the key
fob remote that came with the vehicle.

And the vehicle -- at least from what I can read in the owners manual
-- does not seem to have an "auto lock" function that can be programmed
into the factory installed alarm.

Any thoughts?