Pour in coolant and bleed cooling circuit

AR08.50-S-0017-01F

Pour in coolant and bleed cooling circuit

 Danger

Risk of death when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC)

Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.

AS00.00-Z-0035-01A

 Warning

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

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

Topical note

Notes on battery

AH54.10-P-0001-01A

Topical note

General information on vehicles with high-voltage on-board electrical system and/or lithium-ion battery and/or gaseous-fuel drive system as well as personal protective equipment

AH00.00-Z-0300-01A

Topical note

Notes on coolant

AH20.00-N-2080-01A

Notes on coolant level for high-voltage battery cooling system

AH08.50-S-0051-01F

Notes on coolant level for electric motor cooling system

AH08.50-S-0050-01F

Engine

780.701/702 in model 447

Modification notes

20.07.2020

Method modified.

Operation steps 36, 40, 41, 42, 43, 44, 45

20.07.2020

Special tool 124 589 24 21 00 pressure pump added.

Operation steps 40, 41, 43, 44

 Cooling system

Number

Designation

Engine 780.701/702 in model 447

BF08.50-N-1001-01F

Electric drive cooling system

Cooling system of high-voltage battery and vehicle interior

Filling capacity

Liter

 10

Cooling system of electric motor

Filling capacity

Liter

 5

For both cooling systems, entire filling capacity, in the workshop

Filling capacity

Liter

 15

Antifreeze/water

Down to -37 °C

%

50/50

Coolant specifications

BB00.40-P-0310-01A

Sheet

BB00.40-P-0325-05A

1

Fill specified coolant in sufficient filling quantity   into coolant reservoir (7).

 The fill level in the coolant reservoir (7) must exceed the maximum filling capacity of the respective cooling circuit by approx. 30%.
 Vacuum-type cooling system filler will otherwise intake air into cooling circuit.

2

Place coolant reservoir (7) onto a horizontal surface and note down the fill level.

3.1

If the cooling circuit of the high-voltage battery is filled.
Attach  tester cap (1) to coolant expansion reservoir (31) for cooling system of high-voltage battery.

 The vehicle has two cooling circuits that are separate from one other; one for the cooling system of the electric motor and one for the cooling system of the high-voltage battery.

3.2

If the cooling circuit of the electric motor is filled.
Attach  tester cap (1) to coolant expansion reservoir (30) of cooling system of electric motor.

 The vehicle has two cooling circuits that are separate from one other; one for the cooling system of the electric motor and one for the cooling system of the high-voltage battery.

4

Attach control unit (2) to the  tester cap (1).

5

Attach venturi nozzle (3) to the control unit (2).

6

Close feed valve (4) and drain valve (5).

7

Attach feed hose (6) to the coolant reservoir (7).

8

Insert waste air hose (8) into an empty container.

9

Connect a compressed-air hose (9) to the venturi nozzle (3) and apply compressed air.

10

Open drain valve (5).

11

Open the feed valve (4) until the feed hose (6) has been filled with coolant from the coolant reservoir (7).

12

Close drain valve (5) if the display of the controller unit (2) is in the green area.

13

Remove compressed-air hose (9) from the venturi nozzle (3).

14

Check whether the vacuum on the display of the controller unit (2) remains stable for approx. 30 s.

If the vacuum does not remain stable,



Check hoses, connections, and component parts of the corresponding cooling circuit, rectify causes, and restart evacuation.

15

Empty the drainage tank in the  NTKL adaptation (13).

16

Switch the switch (11) of the  electrical vacuum pump (18) into the "0" position.

17

Connect POSITIVE and NEGATIVE terminals of  electric vacuum pump (18) with a suitable 12 V voltage source (e. g. an on-board electrical system battery).

 Observe polarity of POSITIVE and NEGATIVE terminals.

18

Hook the bracket (12) as shown into the  NTKL adaptation (13).

19

Attach the hose (14) to the  NTKL adaptation (13).

20

Close the stopcocks (15, 16, 17).

21

Attach the hose (20) to the  NTKL adaptation (13).

22

Remove Y-distributor from hose (20).

23

Remove the venturi nozzle (3) from the controller unit (2).

24

Attach the hose (20) to the controller unit (2).

 Fasten the hose (20) to the connection fitting using a suitable clamp.

25

 Switch on the electric vacuum pump (18) with the switch (11).

26

Open the stopcock (15).

 The feed valve (4) remains closed.

 Vacuum indicator (19) must at least show -0.9 bar.

If -0.9 bar is not reached,



Check cause, rectify it, and set up vacuum again.

27

Open the drain valve (5) and evacuate the cooling circuit for approx. 5 min.

 In this connection, observe vacuum indicator (19).
The vacuum must remain stable at -0.9 bar.

If the vacuum does not remain stable,



Check hoses, connections and component parts of cooling circuit, eliminate causes and restart evacuation.

28

Close drain valve (5).

29

 Switch off electric vacuum pump (18) with the switch (11).

30

Remove hose (14) from the  NTKL adaptation (13).

 Vacuum in  NTKL adaptation (13) is thereby reduced until vacuum indicator (19) shows 0.0 bar.

31

Based on the indicator of the control unit (2), check whether the vacuum remains stable for 30 s.

If the vacuum does not remain stable,



Check hoses, connections and component parts of cooling circuit, eliminate causes and restart evacuation.

32

Open feed valve (4).

 The corresponding cooling circuit will now be filled.
The filling process ends when the indicator of the control unit (2) reaches 0.0 bar.

33

Open the drain valve (5) as soon as coolant is no longer flowing into the cooling circuit.

 The remaining existing vacuum will be removed in this way.

34

Place the coolant reservoir (7) onto a horizontal surface.

35

Compare the fill level of the coolant reservoir (7) with the noted fill level.

 The filled in coolant quantity of cooling circuit should be > 75% of filling capacity.
Malfunctions can otherwise occur during the subsequent ventilation.

If less than 75% of coolant filling capacity was filled,



drain coolant again and repeat entire process.

36

Remove controller unit (2) with all connections.

  Do not yet remove tester cap (1).

37

Remove hose (20) from the controller unit (2).

38

Attach Y-distributor to hose (20).

 Replace clamp.

39

 Remove electric vacuum pump (18) from the  NTKL adaptation (13).

40

 Attach pressure pump (10) to  tester cap (1).

41

Using  pressure pump (10), generate a pressure of 1 to 1.5 bar.

42.1

If the cooling circuit of the high-voltage battery is bled.
Bleed cooling circuit of high-voltage battery using the vehicle diagnosis system.

 The electric coolant pumps are released automatically when they are bled.
The duration of the bleeding process of the cooling circuit of the high-voltage battery is approx. 30 min.

 Fully execute the procedure for bleeding the high-voltage battery cooling circuit.
To do so, select following menu items:
Powertrain (CPC) 
Special procedures 
Bleeding of passenger compartment high-voltage battery coolant circuit

42.2

If the cooling circuit of the electric drive is bled.
Bleed cooling circuit for electric drive using the vehicle diagnosis system.

 Fully execute the specified procedure for bleeding the cooling circuit for the electric drive.
To do so, select following menu items:
Powertrain (CPC) 
Special procedures 
Bleeding of coolant circuit for electric drive

 The electric coolant pumps are released automatically when they are bled.
The duration of the bleeding process of the cooling circuit for the electric drive is approx. 15 min.

43

Reduce pressure at  pressure pump (10).

44

 Remove pressure pump (10) from  tester cap (1).

45.1

If cooling circuit of electric motor was filled.
 Remove tester cap (1) from coolant expansion reservoir (30) of cooling system of electric motor.

45.2

If cooling circuit of high-voltage battery was filled.
 Remove tester cap (1) from coolant expansion reservoir (31) of cooling system of high-voltage battery.