2007 Mercedes S-Class Owner's Manual - Page 499

Operation Engine compartment Using a rag, turn cap 1 slowly approximately one half turn counterclockwise to release any excess pressure. Continue turning the cap counterclockwise and remove it. The coolant level is correct if the level for cold coolant: reaches the white marking (plastic bridge) inside the coolant expansion tank for warm coolant: is approximately 0.6 in (1.5 cm) higher Add coolant as required. Replace and tighten cap 1. For more information on coolant, see the "Technical data" section ( page 665). S 550 with Airmatic Using a rag, slowly open the cap approximately 1/2 turn to relieve excess pressure. If opened immediately, scalding hot fluid and steam will be blown out under pressure. Do not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may burn if it comes into contact with hot engine parts. Windshield washer system and headlamp cleaning system The washer fluid reservoir is located on the left-hand side of the engine compartment when looking in the direction of travel. It supplies the windshield washer system and headlamp cleaning system* with washer fluid. The coolant expansion tank is located on the passenger side of the engine compartment. 1 Cap Example illustration from S 550 1 Cap 2 Coolant expansion tank 498