locks on the 91's
 

I have searched and can't find much. I know this is a big problem lots have had. My passenger lock won't lock automaticlly. If you push it down it will lock the rest thought. It does not matter if it is cold. I have searched and found 91's don't have the door lock timer so is this a problem with the actuator? If it is can it be resoldered? Any info will help thanks. I would like to hear if anyone else has fixed it before.
Jon