First you should check your fuses to insure you haven't blown a fuse. Also check to be sure your battery is charged and/or your converter is working.
Looking at pictures of the Mallard M25, it would appear that you have a cable operated slide. So the motor would typically be located behind the fascia at the top. You probably have to remove the fascia to get back there.
Check out this video. The cable slide portion starts at about 3.5 minutes in.
https://www.youtube.com/watch?v=H0ETwE3SrCM