2003 Mercedes S-Class Owner's Manual - Page 268

Operation Engine compartment Transmission fluid level The transmission fluid level does not need to be checked. If you notice transmission fluid loss or gear shifting malfunctions, have an authorized Mercedes-Benz Center check the automatic transmission. Active Body Control* (ABC*) fluid level Regular fluid level check is not required. If you notice fluid leaks or malfunction messages in the multifunction display, have an authorized Mercedes-Benz Center check the ABC-system. Coolant The engine coolant is a mixture of water and anticorrosion/antifreeze. To check the coolant level, the vehicle must be parked on level ground and the engine must be cool. Warning! G In order to avoid any possibly serious burns: Use extreme caution when opening the hood if there are any signs of steam or coolant leaking from the cooling system, or if the coolant temperature gauge indicates that the coolant is overheated. Do not remove pressure cap on coolant reservoir if engine temperature is above 194°F (90°C). Allow engine to cool down before removing cap. The coolant reservoir contains hot fluid and is under pressure. 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. 268