Problems with lane assist and heating in the Audi A6

For the heater error message, start by checking the fuse related to the lane assist system's heater. A blown fuse could be causing the malfunction. If the fuse is intact, inspect the wiring and connections for any signs of damage or corrosion. Regarding deactivating the lane assist system, while it might be possible to turn off the system through the vehicle's settings, it likely won't suppress the error message if there's a fault in the system. It's best to address the root cause of the error. Please let me know if you have any further questions or if you need more assistance.