Remove/install coolant circuit heater of high-voltage battery cooling system

AR08.50-S-0004F

Remove/install coolant circuit heater of high-voltage battery cooling system

17.02.2020

Engine

780.701 in model 447

1

Heater unit

6

Bracket

10

Line bracket

2

Coolant hoses

7

Line bracket

11

Electrical wiring harness

3

Nut

8

High-voltage line

12

Locking element

4

Equipotential bonding line

9

Line bracket

13

High-voltage plug

5

Bolts

1

Heater unit

14

Bolts

8

High-voltage line

15

Electrical connector

 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

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

Information on preventing damage to electronic components due to electrostatic discharge

AH54.00-P-0001-01A

 

Remove/install

1

Drain coolant for high-voltage battery cooling system.

AR08.50-S-0021F

2

Remove voltage of high-voltage on-board electrical system.

AR47.70-S-1000F

3

Store transmitter key outside the transmitter range (at least 2 m).

4

Remove cross strut.

AR61.10-S-5139F

5

Release high-voltage battery coolant circuit switchover valve at underbody and place with connected coolant hoses to one side.

AR08.50-S-0000F

6

Remove coolant hoses (2) from heater (1).

 Collect escaping coolant.

 Hose clamp pliers

*454589003700

7

Seal openings with suitable stop plug.

 Record plug

*129589009100

8

Unscrew nut (3) and disconnect equipotential bonding line (4).

 Nut, potential equalization ground line to bracket of coolant circuit heater for high-voltage battery

*BA47.70-N-1008-02F

9

Unclip line bracket (7) of high voltage line (8) from bracket (6).

 Clip remover

*452589016300

10

Unclip line bracket (9) from bracket (6) and place equipotential bonding line (4) to one side.

 Clip remover

*452589016300

11

Unclip line bracket (10) of electrical wiring harness (11) from bracket (6).

 Clip remover

*452589016300

12

Release locking element (12).

 WIS Service Media
wsm://04_ 201800_30
Operation steps 12 and 13 are shown.

13

Release high-voltage plug (13) on both sides and disconnect.

14

Cover electrical connections with suitable protective covers.

 Set of protective covers

*001589019100

15

Remove screws (5) and detach holder (6).

16

Remove screws (14).

 Screw, coolant circuit heater to holder

*BA08.50-N-1001-03F

17

Remove heater (1) with high voltage line (8) until electrical connector (15) can be accessed.

 WIS Service Media
wsm://04_201800_29
Operation steps 17 to 19 are shown.

18

Release and disconnect electrical connector (15).

19

Remove heater (1) with installed high voltage line (8) and equipotential bonding line (4).

20

Check equipotential bonding line (4) for heater (1).

AR47.70-S-1020-01F

 Nut, potential equalization ground line to coolant circuit heater for high-voltage battery

*BA47.70-N-1009-02F

21

Disconnect high voltage line (8) from heater (1).

If heater (1) is replaced.

22

Cover electrical connections with suitable protective covers.

If heater (1) is replaced.

 Set of protective covers

*001589019100

23

Remove equipotential bonding line (4) from heater (1).

If heater (1) is replaced.

 Nut, potential equalization ground line to coolant circuit heater for high-voltage battery

*BA47.70-N-1009-02F

24

Install in the reverse order

25

Check high-voltage battery cooling system in area of heater (1) for leaks.

AR08.50-S-0011F

26

Perform commissioning of heater (1) with vehicle diagnosis system.

If heater (1) is replaced.



AD00.00-S-2000-04E

 Heater of high-voltage battery cooling system

Number

Designation

Engine 780.701/702 in model 447

BA08.50-N-1001-03F

Screw, coolant circuit heater to holder

Nm

7

 High-voltage on-board electrical system potential equalization ground lines

Number

Designation

Engine 780.701 in model 447

BA47.70-N-1008-02F

Nut, potential equalization ground line to bracket of coolant circuit heater for high-voltage battery

Nm

7

 High-voltage on-board electrical system potential equalization ground lines

Number

Designation

Engine 780.701 in model 447

BA47.70-N-1009-02F

Nut, potential equalization ground line to coolant circuit heater for high-voltage battery

Nm

7