Remove/install cooler of high-voltage battery cooling system

AR08.50-P-0126RFW

Remove/install cooler of high-voltage battery cooling system

28.11.2018

Engine

780 in model 253.992/993

A

Fuel cell cover

1a

Intake air duct

1b

Expansion rivet

1c

Expansion rivet

1d

Cold air intake

2a

Screws

2e

Insert fastener

2b

Screw

2f

Screws

2c

Screws

2g

Front module carrier

2d

Screw

1

Screw

4

Screws

2

Screws

5

Screw

3

Front mounting support

6

Rear mounting support

7

Line clips

12

Nuts

17

Screw

8

Wiring harness

13

Screw

18

Evaporator

9

Line bracket

14

Bracket

M75/10

High-voltage battery coolant pump

10

Screw

15

Crossmember

11

Cross strut

16

Screws

15

Crossmember

21

High-voltage battery cooler

19

Coolant line

22

Air duct segment

20

Coolant line

23

Electrical connector

6

Rear mounting support

22b

Mounting clip

22

Air duct segment

21

High-voltage battery cooler

25

Guides

24

Latching

26

Basic carrier

 Danger

Risk of explosion caused by escaping hydrogen or overheating of the fuel tanks when working on the hydrogen system. Risk of frostbite to body parts caused by escaping gas and by touching component parts carrying gas when emptying fuel tanks. Risk of asphyxiation caused by inhalation of air diluted by hydrogen. Risk of burn injuries by coming into contact with an invisible pale blue hydrogen flame.

AS00.00-Z-0030-01B

 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

 Caution

Risk of injury caused by scraping or cutting body parts on sharp vehicle parts

Always wear protective gloves when working on or near sharp and non-deburred vehicle parts.
Deburr repair panels.

AS00.00-Z-0017-01A

Topical note

Notes on bolted connections with self tapping screws

AH00.00-P-0007-01SF

Topical note

Notes on fuel cell system

AH00.00-P-0022-01RFW

Topical note

Notes on coolant

AH20.00-N-2080-01A

 

Remove/install

1

Ensure that the requirements for driving into the workshop are fulfilled.

Topical note

Requirements for driving into the workshop

AH00.00-P-0021-01RFW

2

Print out "tank system, fuel cell form event log," fill out, and attach to the vehicle somewhere clearly visible.



OF00.00-P-3000-21RFW

3

Remove fuel cell cover (A).

4

Remove intake air duct (1a).

5

Remove expansion rivets (1b, 1c) and take out cold air intake (1d).

 Clip remover

*452589016300

6

Remove lamp units.

AR82.10-P-4730LW

7

Remove screws (2a, 2b, 2c, 2d).

 M61

*BA00.10-P-1002-04A

 Bolt, strut to cross member

*BA62.30-P-1003-01H

 Bolt, lock striker to cross member/front-module carrier

*BA62.30-P-1008-01H

8

Release insert fasteners (2e) and remove.

9

Remove screws (2f).

 M61

*BA00.10-P-1002-04A

10

Remove front module carrier (2g).

11

Remove front engine compartment lining.

AR61.20-P-1105LW

 Installation: Only install front engine compartment lining after leak test.

12

Drain high-voltage battery cooling system coolant.

AR08.50-P-0021RFW

13

Unscrew screws (1).

 Screw, rear mounting support to assembly carrier

*BA62.30-P-1014-01H

14

Loosen screws (2) and pull front mounting supports (3) forward.

 Loosen screws (2) until the screws (4) are accessible.

 Screw, front mounting support to rear mounting support

*BA62.30-P-1012-01H

15

Unscrew screws (4).

Topical note

Notes on threaded connections fastened using a tightening angle-based tightening process

AH00.00-P-0020-01A

 Installation: Replace right screw (4).

 Bolt, cross member to soundproofing

*BA62.30-P-1001-01H

16

Remove screws (5).

 Screw, rear mounting support to crossmember

*BA62.30-P-1013-01H

17

Place left and right rear mounting support (6) to one side.

18

Unfasten line clips (7) and line bracket (9) for wiring harness (8).

Engine 780 in model 253.992/993
with code 233 (DISTRONIC PLUS)
Engine 780 in model 253.992/993
with code 239 (Active Distance Assist DISTRONIC)

19

Remove screws (10) and take off cross strut (11).

 Screw, cross strut/crossmember to holder

*BA62.30-P-1011-01H

20

Unscrew nuts (12).

 Bolt/nut, bracket for compressor unit to body/cross member

*BA32.22-P-1002-03G

21

Remove screw (13) and move bracket (14) towards rear.

 Carefully lever holder (14) of high-voltage battery coolant pump (M75/10) over edge of the crossmember (15).

 Bolt, bracket for coolant pump for high-voltage battery cooling to body

*BA20.50-P-1002-01C

22

Remove screws (16, 17) for evaporator (18).

 Bolt, bracket for heat exchanger for high-voltage battery cooling to body

*BA20.50-P-1005-01C

23

Remove coolant line (19, 20) from high-voltage battery cooler (21).

AR20.20-P-7441-01RQ

 Collect escaping coolant in a suitable vessel.

24

Seal openings using stop plugs.

 Record plug

*129589009100

25

Unhook coolant line (20) on air duct segment (22).

26

Disconnect electrical connector (23).

27

Pull crossmember (15) on the left forward slightly.

 Carefully pull crossmember (15) forward and be mindful of clearance.

 Aid of helper required.

28

Release left air duct segment (22) at the mounting clips (22b) and pull up and out.

29

Release high-voltage battery cooler (21) at catch (24) and guides (25) on basic carrier (26) and remove.


Remove high-voltage battery cooler (21) carefully.
Otherwise, the cooler connections or high-voltage battery cooler (21) will be damaged.

30

Install in the reverse order.

31

Refill coolant and bleed fuel cell cooling system.

AR08.50-P-0021RFW

32

Install front engine compartment lining.

AR61.20-P-1105LW

 Metric screws/bolts and nuts as per MBN 10 105, 10 143

Number

Designation

8.8

10.9

BA00.10-P-1002-04A

M61

Nm

9

13

 Heat exchanger

Number

Designation

Model 253
with code ME02 (Fuel cell)

Model 253
with code ME05 (HYBRID DRIVE 80KW VARIANT (INCLUDING PLUGIN))

BA20.50-P-1002-01C

Bolt, bracket for coolant pump for high-voltage battery cooling to body

Nm

12

12

 Heat exchanger

Number

Designation

Model 253
with code ME02 (Fuel cell)

Model 253
with code ME05 (HYBRID DRIVE 80KW VARIANT (INCLUDING PLUGIN))

BA20.50-P-1005-01C

Bolt, bracket for heat exchanger for high-voltage battery cooling to body

M6

Nm

8

8

M8

Nm

12

12

 Air suspension

Number

Designation

Model 253

BA32.22-P-1002-03G

Bolt/nut, bracket for compressor unit to body/cross member

Nm

20

 Cross member and front reinforcement

Number

Designation

Model 253

BA62.30-P-1001-01H

Bolt, cross member to soundproofing

M10

Stage 1

Left side

Nm

28

Right side

Nm

35

Stage 2

°

135

 Cross member and front reinforcement

Number

Designation

Model 253

BA62.30-P-1003-01H

Bolt, strut to cross member

M8

Nm

20

 Cross member and front reinforcement

Number

Designation

Model 253

BA62.30-P-1008-01H

Bolt, lock striker to cross member/front-module carrier

Nm

10

 Cross member and front reinforcement

Number

Designation

Model 253

BA62.30-P-1011-01H

Screw, cross strut/crossmember to holder

M8

Nm

20

 Cross member and front reinforcement

Number

Designation

Model 253

BA62.30-P-1012-01H

Screw, front mounting support to rear mounting support

Nm

8

 Cross member and front reinforcement

Number

Designation

Model 253

BA62.30-P-1013-01H

Screw, rear mounting support to crossmember

Nm

3

 Cross member and front reinforcement

Number

Designation

Model 253

BA62.30-P-1014-01H

Screw, rear mounting support to assembly carrier

Nm

7