Ron Natalie wrote:
My autopilot has both pitch servos and trim. You push on the yoke
it has the same impact that it would if the autopilot wasn't there.
However, what the autopilot does endeavor to do is adjust the trim
so that it's always "trimmed" which means it may try to trim away
your force (if you are pitching it away from where it thinks it
should be). The autopilot does this so that if you kick off the
autopilot it's giving you a plane that is in trim.

Some autopilots don't have trim servos and have "up" and "down"lights
on the autopilot display asking the pilot to retrim. The autopilot
normally flys a bit out of trim but anything outside the params results
in a request of the pilot to trim. The purpose is just as you
mentioned. You would be sad to find yourself in a nose down dive after
disconnecting the autopilot.
The autopilots that have "pitch control" (terminology used to denote
that it does more than hold altitude, it holds VS) usually have trim
control as well. The familiar "Trim, in motion" annunciator that seems
to go off everytime I click the mic to call tower in the G1000
aircraft.

-Robert