Jumper door lock failure

Sounds familiar. I had a similar issue with my Jumper, though it wasn't an electric one. Check the wiring harness and plugs to the door sensor. A defective cable or plug connection can cause this. It's worth a look before you start tearing things apart.

Thanks! Where exactly is the door sensor located? And is there a specific plug connection I should be looking for? Any idea on what a repair like this would cost?

The sensor is usually inside the door near the latch mechanism. As for the plug, follow the wiring harness from the sensor; you'll find it. I'd suggest going to the workshop, better than tinkering around yourself. In my case, the repair cost around 95€, but it depends on the damage.

Thanks a lot for the help! I took it to the workshop, and you were right - the cable to the door sensor was faulty. They replaced it, and everything's working fine now!