Check main circuit coolant level - AP20.30-P-2050B

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ENGINE 780 in MODEL 242

Fig 1: Locating Coolant Expansion Reservoir Cap (Engine 780)

Courtesy of MERCEDES-BENZ USA

	Risk of injury due to fan starting unexpectedly	Do not reach into the rotation or hazard area of the fan. Wear closed and close-fitting work clothes.	AS20.40-Z-0001-01A
	Risk of death when touching components on vehicles with high-voltage on-board electrical system	Do not touch components and open lines of the high-voltage on-board electrical system. Persons who wear electronic implants (e.g. cardiac pacemakers), must not carry out any work on high-voltage on-board electrical systems.	AS54.00-Z-0001-01A
	Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.	Do not open cooling system unless coolant temperature is below 90 °C. Open cap slowly and release the pressure. Do not pour coolant into beverage containers. Wear protective gloves, protective clothing and safety glasses.	AS20.00-Z-0001-01A
	Notes on coolant		AH20.00-N-2080-01A
	Check
1	Check coolant level in light-dark boundary area of coolant expansion reservoir (2)	For coolant expansion reservoirs (2) with transparent tank lower part. Coolant level below light-dark boundary: ↓ Coolant level incorrect, continue with operation step 2. Coolant level above light-dark boundary: ↓ Coolant level correct, coolant level check completed.
	Remove
2	Unscrew cap (1) for coolant expansion reservoir (2)	For an incorrect coolant level.
	Check
3	Check coolant level	For an incorrect coolant level. The coolant level on a cold engine must reach up to the marking (arrow) in the coolant expansion reservoir (2). When the coolant is warm, about 1 cm (0.39 inch) above the marking (arrow). If coolant level is too low: ↓ Check coolant for leaktightness and check coolant for antifreeze content subject to separate repair order.
3	Check coolant level	Coolant mixing ratio	*BF20.00-P-1001-04A
	Install
4	Seal coolant expansion reservoir (2) with cap (1)	For an incorrect coolant level.

COOLANT MIXING RATIO

Number	Designation			ENGINE ALL
BF20.00-P-1001-04A	Coolant mixing ratio	Antifreeze/water	bis -37°C	50/50
		Antifreeze/water	bis -45°C	55/45
		Specifications		Coolant (Specification 310.1). See https://bevo.mercedes-benz.com/index.php?language_id=1