Saxo electric steering fault

Sounds like you've narrowed it down to a connection issue. Have you checked the fuses and relays associated with the electric steering system? A blown fuse could explain the lack of adjustment and the error code.

I checked the fuses and relays, and they're fine. Is there a specific diagnostic procedure I should follow to pinpoint the defective cable or plug? Or should I seek professional help?

Since the fuses and relays are good, it indicates a fault within the electric steering column system. Further diagnostics are possible, but tracing electrical faults can be time-consuming and require special equipment. Considering the car's age and the complexity, a qualified workshop might be best.

I visited a workshop as suggested. It was a defective plug connection. The repair cost 95€. Thanks for the help; it was invaluable.