Mercedes R Klasse Transfer Case Limp Mode

Sounds familiar. I had a similar issue with my Mercedes R Klasse a while back. The symptoms you describe are pretty much spot on with what I experienced. My issue was related to the torque converter acting up due to a faulty ABS sensor throwing the whole system into limp home mode. The car basically limits power to protect itself. Have you checked the wheel speed sensors? A bad sensor can cause all sorts of consequential faults. Also, make sure your battery is healthy, low voltage can cause the ABS to throw errors.

Thanks for the info. How did you diagnose the faulty ABS sensor? Did you need any special tools, or was it something a regular diagnostic tool could pick up? Also, did the diagnostic trouble codes specifically point to the ABS sensor, or were they more general powertrain malfunction codes?

I used a decent scan tool, but you should be able to see ABS related codes with a more basic one too. The codes were kind of vague at first, like 'implausible signal' from one of the wheel speed sensors. I cleared the codes and the ABS light came back on pretty quick. I didn't mess with it myself, I took it to a workshop to sort the diagnostic trouble and the consequential faults. It's a complicated system, and without the right tools and knowledge, you could end up causing more damage. Best to get it checked out by a pro, so they can pinpoint the issue and give you an accurate repair cost estimate.

Thanks for confirming. I appreciate the input. I took it to the workshop, and it turned out to be exactly as you described: an ABS sensor causing the torque converter to act up and putting the car into limp mode. The repair was covered, so it ended up costing me 0€.