2009 Mercedes SL-Class Owner's Manual - Page 210

Operation Engine compartment voir contains hot fluid and is under pressure. RUsing X 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. not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may burn if it comes into contact with hot engine parts. Using a rag, turn the cap slowly approximately 1/2 counterclockwise to release any excess pressure. Continue turning the cap counterclockwise and remove it. The coolant level is correct if the level Rfor Washer system and headlamp cleaning system G Warning! Washer solvent/antifreeze is highly flammable. Do not spill washer solvent/antifreeze on hot engine parts, because it may ignite and burn. You could be seriously burned. ! Always use washer solvent/antifreeze where temperatures may fall below freezing point. Failure to do so could result in damage to the washer system/fluid reservoir. ! Only use washer fluid which is suitable for plastic lenses. Improper washer fluid can damage the plastic lenses of the headlamps. ! Do not use distilled or de-ionized water in the washer fluid reservoir. Otherwise, the washer fluid level sensor could be damaged. X RDo cold coolant: is up to the upper mark on the bracing rib of the coolant expansion tank (translucent) (1.5 cm) higher Rfor warm coolant: is approximately 0.6 in X X Add coolant as required. Replace and tighten cap. ! SL 600 and SL 65 AMG: Only open the cap on the coolant expansion tank. Never open the cap between the two charge-air coolers. Otherwise, the engine could be damaged. For more information on coolant, see the "Technical data" section (Y page 355). 1 Coolant expansion tank 208