Door lock problem on 2000 Jaguar XJ8

I have a 2000 Jaguar XJ8 and the door locks keep locking and unlocking after about 15 minutes of driving (presumably something gets warm or hot). I cannot locate a wiring diagram, and the local Jag people don’t know what the problem is. In the handbook, there is mention of an inersia switch which is somehow connected to the door locks. Has anyone had an experience with this problem, or could point me where to look to rectify the problem.

You may have a similar problem as we (and many others) have seen on our Mercedes SUV. In the MB world it is affectionately known as “Machine Gun Locks”. Perhaps someone here has some good ideas, but try Edmund’s XJ8 area at
http://townhall-talk.edmunds.com/direct/view/ed_displayMakeModelRelatedDiscussions!make=Jaguar&model=XJ-Series

And search “Door Locks”.

In the MB they replace the door lock actuator on whatever door is causing the problem.

I would suspect the driver’s side (since that is the most used) door lock switch has some dirty contacts. It may be unlocking the doors while driving and then the motion system relocks the doors. This process keeps repeating as you drive. To prove this you could disconnect the door switch and see what happens.