Mercedes X Klasse Diesel Transmission Problem

I own an X Klasse as well. While I haven't had the exact same issues, a slipping transmission and check engine light can mean many things. That error code is key. The control unit manages the transmission's operation, including shift points and pressure. A defective transmission sensor could send bad data to the control unit. Also, check the gear linkage for damage or misalignment, though that's less likely with electronic transmissions. Does the error code specifically point to the control unit?

Thanks. I'm not 100% sure about the specific error code, but I remember it was related to transmission control. Can I check the transmission sensor or gear linkage myself? I'm not a mechanic, but I'm willing to look before going to a workshop.

You can visually inspect the gear linkage, but checking the transmission sensor needs special equipment to read its output. Given the symptoms and the error code pointing towards the control unit, it's best to take your X Klasse to a qualified workshop. They can properly diagnose the issue and confirm if the control unit is defective, or if another component, like a faulty sensor, is the root cause. Address transmission issues quickly to avoid further damage.

Thanks I took it to a workshop, and you were right, it was the control unit. They replaced it, and the transmission is shifting smoothly again. The total cost was pretty much what was expected. Appreciate the help!