Drain/fill coolant of auxiliary circuit

AR08.50-D-0022TE

Drain/fill coolant of auxiliary circuit

24.07.2020

Engine

780.703 in model 910

Modification notes

20.07.2020

Special tool 124 589 24 21 00 pressure pump added.

Operation step 25

20.07.2020

Method modified.

Operation steps 34, 38, 39, 40, 41, 42, 43

AR08.50-D-0017-01TE

20.07.2020

Special tool 124 589 24 21 00 pressure pump added.

Operation steps 38, 39, 41, 42

AR08.50-D-0017-01TE

1

Coolant expansion reservoir

2

Cap

3

Connection fitting

4

Switchover valve

5

Connection fitting

6

Bolts

1

Coolant expansion reservoir

7

Tester cap

8

Pressure pump

9

Coolant line

10

Coolant hose

 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 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 avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

Topical note

Notes on coolant

AH20.00-N-2080-01A

Notes on coolant level

AH20.00-P-1142-01CW

Drain off

1

Lock electric coolant pumps with diagnostic system.



Connect/disconnect diagnostic unit

AD00.00-D-2000-06TS


HVAC system must be deactivated (position 0).
Coolant pumps will otherwise be actuated in an unintended manner, which can cause malfunctions.

 Work through specified procedure completely.
To do so, select following menu items:
Powertrain (CPC) 
Actuations 
Locking of coolant pumps.

 Do not yet remove vehicle diagnosis system.

2

Remove cap (2) of coolant expansion reservoir (1).

 First unscrew cap (2) counterclockwise to first detent and release overpressure. Then remove cap (2).

3

Remove lower engine compartment lining

AR61.20-D-1105TS

4

Remove underfloor panels.

AR61.30-D-1001TS

5

Remove underfloor paneling on the right from high-voltage battery module.

AR61.30-D-1002TE

6

Drain coolant from coolant radiator auxiliary circuit.

AR08.50-P-0018-01EQ

 To do so, remove connection fitting (3). Collect all of the escaping coolant.

 Commercially available devices/tools
Collecting pan

7

Lower vehicle.

8

Attach tester cap (7) to coolant expansion reservoir (1).

 Test cap

*210589009100

9

Attach pressure pump (8) to tester cap (7).

 Pressure pump

*124589242100

 Test cap

*210589009100

10

Use pressure pump (8) to generate pressure until coolant no longer escapes.


The coolant radiator auxiliary circuit must be as empty as possible.
Otherwise, filling and later ventilation cannot be performed completely, which can lead to malfunctions and damage.

 Collect coolant.

 Commercially available devices/tools
Collecting pan

 Pressure pump

*124589242100

11

Raise vehicle.

12

Attach connection fitting (3).

AR08.50-P-0018-01EQ

13

Remove screw/bolts (6).

14

Drain coolant at switchover valve (4) of auxiliary circuit.

AR08.50-P-0018-01EQ

 To do so, remove connection fittings (5) from switchover valve (4). Collect all of the escaping coolant.

 Commercially available devices/tools
Collecting pan

15

Drain residual coolant at coolant line (9) of high-voltage batteries.

 To do so, remove coolant hose (10) from coolant line (9). Collect all of the escaping coolant.

 Commercially available devices/tools
Collecting pan

 Hose clamp pliers

*454589003700

16

Attach connection fittings (5) to switchover valve (4).

AR08.50-P-0018-01EQ

17

Screw in bolts (6).

 M6

*BA00.10-N-1002-01A

18

Lower vehicle.

19

Use pressure pump (8) to generate pressure until coolant no longer escapes.


The coolant circuit of the high-voltage batteries must be as empty as possible.
Otherwise, filling and later ventilation cannot be performed completely, which can lead to malfunctions and damage.

 Collect coolant.

 Commercially available devices/tools
Collecting pan

 Pressure pump

*124589242100

20

Remove pressure pump (8) from tester cap (7).

 Pressure pump

*124589242100

 Test cap

*210589009100

21

Remove tester cap (7) from coolant expansion reservoir (1).

 Test cap

*210589009100

22

Raise vehicle.

23

Attach coolant hose (10) to coolant line (9).

 Check clamp for damage.

 Hose clamp pliers

*454589003700

If damage is present,



Replace clamp.

24

Lower vehicle.

Pour in

25

Fill coolant into coolant expansion reservoir (1).

AR08.50-D-0017-01TE


To do this, the auxiliary circuit must be as empty as possible.
Otherwise, filling and later ventilation cannot be performed completely, which can lead to malfunctions and damage.

 Filling capacity for cooling system

*BF08.50-N-1001-01TE

 Test cap

*210589009100

 Cooler vacuum filling device

*285589002100

 NTKL Adaption

*285589012100

 Electric vacuum pump

*285589022100

 Pressure pump

*124589242100

26

Attach charger to 12 volt on-board electrical system battery.

AR54.10-D-1127TS

 It takes approx. 30 min. to bleed the auxiliary circuit with the diagnostic system. A constant 12-volt power supply is required for this.

27

Bleed auxiliary circuit.

AR08.50-D-0017-01TE


Observe specified procedure at all times.
Duration of bleed process can otherwise increase significantly.

 Electric coolant pumps are automatically released during the bleed process.
Work through specified procedure completely.

If high-voltage on-board electrical system is not in operation:



Put the high-voltage on-board electrical system into operation.

AR47.70-D-1000TE

28

Remove vehicle diagnosis system.



Connect/disconnect diagnostic unit

AD00.00-D-2000-06TS

29

Remove charger from 12 volt on-board electrical system battery.

AR54.10-D-1127TS



Check

30

Check coolant level.

If coolant level incorrect



Correct coolant level.

 Filling capacity for cooling system

*BF08.50-N-1001-01TE

31

Check auxiliary circuit for leak tightness.

AR08.50-D-0014TE

 Headless screws/bolts: screws/bolts and nuts, coarse-pitch thread

Number

Designation

8.8

10.9

BA00.10-N-1002-01A

M6

Galvanized

Nm

9

13

Phosphated

Nm

9

12

 Headless screws/bolts: screws/bolts and nuts, coarse-pitch thread

Number

Designation

12.9

BA00.10-N-1002-01A

M6

Galvanized

Nm

16

Phosphated

Nm

14

 Cooling system

Number

Designation

Engine 780.703 in model 910

BF08.50-N-1001-01TE

Filling capacity for cooling system

Main circuit

l

 4,8

Auxiliary circuit with 3 high-voltage batteries

l

 9,6

Auxiliary circuit with 4 high-voltage batteries

l

 10,4

Main circuit and auxiliary circuit with 3 high-voltage batteries in repair case

l

 14,4

Main circuit and auxiliary circuit with 4 high-voltage batteries in repair case

l

 15,2

Mixing ratio for antifreeze/water (to -37 °C)

%

50/50

Coolant specifications

BB00.40-P-0310-01A

Specification

BB00.40-P-0325-05A