2003 Mercedes ML-Class Owner's Manual - Page 230

Practical hints What to do if ... Problem Possible cause The yellow coolant warning lamp The coolant is to hot. lights up when the engine is runThe coolant level is too low. ning. If the warning lamp lights up frequently, there is a leak in the cooling system. The coolant temperature gauge is above 248°F (120°C). The coolant level is too low. Suggested solution Stop as soon as possible and allow the engine and coolant to cool down. Check the coolant level and add coolant if necessary ( page 206). Have the cooling system checked by an authorized Mercedes-Benz Light Truck Center. Stop as soon as possible and allow the engine and coolant to cool down. Add coolant to prevent engine from overheating ( page 206). If the coolant level is correct, the electrical radiator fan may be broken. If the coolant temperature is below the red zone, drive on to the nearest authorized Mercedes-Benz Light Truck Center. Avoid high engine loads (e.g. driving uphill) and stop-and-go driving. / 230