Preface = by automatically locking I mean having the doors lock when the vehicle gets moving. I don't need the doors to lock on their own when we leave the vehicle. No problem pressing a button on the remote to accomplish that.

We lost the remote for the Ram van so I fitted an aftermarket RKE unit in parallel with the factory RKE. The aftermarket RKE has a goofy autolock feature that takes a +12V trigger. Energized = lock, unenergized = unlock. I prefer the Caravan factory system that locks the doors at 17mph but doesn't unlock the doors on its own. The Caravan integrated body control module will be hell to retrofit in the Ram.

What can I do to have a similar autolock feature in the Ram? I've been futzing with triggers and relays in my mind but I can't come up with a combination that will energize the trigger wire and keep it energized until the doors are manually unlocked. Positive trigger to lock and unlock, BTW. Ideally it will lock the first time the shifter goes out of park. I should be able to fit a momentary switch along the shift lever path or a switch that's closed only in park.

Ideas?

Thanks,
Sixto