WARNING: This page is about a different car, the 1992 Mercedes-Benz 300SE. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Coolant Temperature Sensor Connector Terminal I.D.
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Fig 2: Locating Coolant & Intake Air Temp. Sensor Connectors