Door lock gremlins

[Elizabeth]

The door locks on my Grenadier activate (meaning lock, unlock, relock, etc) when the vehicle is moving at between 11 and 13 mph. For example, if I am driving slowly through a parking lot (at between 11 and 13 mph) the door locks will cycle through lock unlock repeatedly until the speed increase or decreases beyond 11-13 mph. Anyone else experiencing this? How to fix it? The shop is stumped.

 

[255/85]

If you've previously locked the door will it unlock at those speeds or does it only happen if starting from an unlocked setting?

 

[Elizabeth]

It happens regardless. I can get in and lock it manually and then at those speeds it clicks clicks clicks as if trying to unlock / lock.

 

[Elizabeth]

Or I can get in and not lock the car and then at those speeds it starts locking unlocking