Engine overheating (Mercedes-Benz Sprinter 903)

If the indicator goes into the red zone only briefly, this is normal for the following operating modes: at maximum speed, driving uphill or in a column in hot weather, after stopping a hot engine, in a "traffic jam" in a car with an automatic transmission (due to the transmission oil cooler - to prevent this, you need to move the lever to N·mode more often).

If the temperature gauge is in the red zone, you should stop, turn off the engine and check the following:

• integrity of the coolant pump drive belt;
• coolant level;
• check the thermostat, if it is jammed the radiator will be noticeably colder than the thermostat housing;
• does the fan turn on?.

If all checks reveal no faults, the radiator is clogged and should be replaced.

Information copied from the website [MercedesMAN.ru]