Remove/install heater housing

AR83.25-P-1000SM

Remove/install heater housing

15.01.2019

Model

450.3/4

1

Connector

5

Door wiring harness

9

Rubber grommet

2

Cable tie

6

Screw cover strip

M5/1

Window washer pump

3

Front water hose

7

Coolant hose

4

Assembly stop

8

Coolant hose

10

Cover

11

Line

S15/1

Remote trunk lid release switch

12

Heating cable

15

Lever

18

Lever

13

Heater housing

16

Air distribution cable

19

Connector

14

Catch

17

Catch

20

Connector

13

Heater housing

23

Bolts

26

Crossmember assembly wedge

21

Bolts

24

Vertical strut

27

Nut

22

Cross member

25

Bolts

 

Remove/install

Topical note

Notes on bolted connections with self tapping screws

AH00.00-P-0007-01SF

1

Remove air splitter

On model 450.3 with code (P07) smart business (Truck registration in France) (FFO)

AR68.74-P-1100SM

2

Disconnect battery ground line

AR54.10-P-0003SM

3

Remove PTC heater booster

On vehicles with engine 660.940

AR83.70-P-8000SM

4

Remove front module

AR62.30-P-1575SM

5

Detach plug (1) from window washer pump (M5/1) and remove cable tie (2)

 Observe catch tabs.

6

Detach front water hose (3) from window washer pump (M5/1) for front windshield washer nozzles and seal connection using a suitable hose piece

7

Detach rear window washer pump from water hose (M5/1) for rear windshield washer nozzles and seal connection using a suitable hose piece

On model 450.3

8

Installation position of left and right mark assembly stops(4)

9

Unhook door wiring harness (5) from assembly stops (4)

10

Remove bolts for assembly stops (4) at left and right and remove assembly stops (4)

11

Detach bolt covers (6) under the assembly stops (4)

12

Remove coolant hoses (7, 8) from heater core


Avoid applying any radial force to pipe socket on heater box (13),
otherwise there is a risk of breakage.

 Installation: Moisten the coolant hoses (7, 8) before installation.

13

Remove rubber grommets (9)

 Installation: Check rubber grommets (9), replace if necessary.

14

Remove air recirculation unit

Model 450.3## 1# , 450.4## (except 450.418) 1#

AR83.10-P-0100SM

Model 450.3## 1#, 450.4## (except 450.418) 1# with code (I01) or code (I29)

AR83.10-P-0100SO

Model 450.3## 2#, 450.4## (except 450.418) 2# except code I01o or code I29

AR83.10-P-0100SN

Model 450.3## 2#, 450.4## (except 450.418) 2# with code (I01) or code (I29)

AR83.10-P-0100SP

15

Remove left sound converter box

AR82.60-P-1100SM

16

Remove remote trunk lid release switch (S15/1)

Only on model 450.3 as of 15.11.99

17

Remove cover (10)

18

Unclip line (11)

19

Unhook heating cable (12) from heater box (13)

 Installation: Insert heating cable (12) into catch (14) then hook onto lower lever (15).
Adjust heating cable (12)
Release heating cable (12) from catch (14) on lower lever (15) on heater box (13).
Pull lever on heater/ventilation operating unit to left up to end stop and hold.
Slide lower lever (15) on heater box (13) upwards to the end stop and lock heater cable sleeve (12) in place.
Carry out function test.

20

Unhook air distribution cable (16) from heater box (13)

 Installation: Insert air distribution cable (16) into catch (17) and hook into upper lever (18).
Adjust air distribution cable (16)
Release air distribution cable (16) from catch (17) on upper lever (18) on heater box (13).
Pull lever on heater/ventilation operating unit to left up to end stop and hold.
Pull upper lever (18) on heater box (13) upwards to end stop and lock air distribution cable sleeve (16) in place.
Carry out function test.

21

Detach plugs (19, 20)

 Observe catch tabs.

22

Remove bolts (21) from crossmember (22)

 If the thread in the crossmember (22) fails, in some cases, a special repair solution is available.
Please contact the service hotline.

23

Remove bolts (23) from vertical strut (24) on crossmember (22)

 Installation: Replace bolts (23).

 Bolt for vertical strut to crossmember

*BA62.30-P-1002-02B

24

Remove bolts (25) from crossmember (22) on A-pillar on both sides

 Bolt for crossmember on A-pillars

*BA62.30-P-1001-02B

25

Remove crossmember mounting wedge (26)

 Installation:



Position crossmember (22)

AR62.30-P-1250-01SM

 Dial indicator with accessories

*450589062100

 Punch

*450589021500

26

Slide crossmember (22) far enough to one side until heater box (13) is accessible

27

Remove nut (27) and remove heater box (13)

When replacing the heater box (13)



Modify blower motor

AR83.25-P-1200SM

Modify series resistor for heater blower

AR83.25-P-1250SM

28

Install in the reverse order

 Front end with front reinforcement

Number

Designation

Model 450.3/4

BA62.30-P-1001-02B

Bolt for crossmember on A-pillars

Nm

25

 Front end with front reinforcement

Number

Designation

Model 450.3/4

BA62.30-P-1002-02B

Bolt for vertical strut to crossmember

Nm

8