E Klasse electric steering column issue

That sounds frustrating. I had a similar adjustment issue with my old Saab, though it wasn't the steering column itself, but the seat adjustment. It turned out to be a dodgy connection in the wiring harness. Think of it like a Christmas tree light where one bulb being loose kills the whole string. Have you checked all the plugs and cables leading to the steering column motor?

Where exactly should I be looking for these connections?

Okay, so on my Saab, the connections were under the seat. Your Mercedes might be similar, look under the steering column trim, where the adjustment motor is located. But honestly, for 95€, it's probably worth having a workshop take a peek. They'll have the right tools and diagrams to pinpoint the issue quickly and avoid you messing something up further.

Thanks. I took it to a workshop, just as you suggested. They found a loose connection, just like the error memory suggested. The final repair bill was indeed 95€. All sorted now.