A common issue with older BMWs is the failure of some plastic connectors for non-critical sensors. I believe this was due to German regulations forcing biodegradable plastics use during the 80's and 90's. Whether or not it was intentional, they commonly become extremely brittle and fall apart.
This would be a rather straightforward fix - buy new connector shells and install - but there is an overmolded plastic part that surrounds the pins which also has a tenancy to crumble.
This 3d printed part replaces that overmolded portion to allow the pins to seat correctly in the connector.
Make sure to print many parts at once time to prevent overheating the layers