Remove/install heater unit

AR83.70-P-5302PB

Remove/install heater unit

7.9.10

 

Remove/Install

1.1

Remove bottom section of front noise encapsulation

Engine 611, 612

AR94.30-P-5300P

1.2

Remove front engine compartment paneling

Engine 111, 112, 113

AR61.20-P-1105P

2

Remove right front wheelhousing liner

3

Remove right front wheel

4

Remove front bumper

Model 203 except 203.076 / 276

AR88.20-P-2000P

Model 203.076/ 276

AR88.20-P-2000Q

 Danger!

Risk of injury to skin and eyes suffering scalding from contact with hot coolant spray. 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 bottles.

Wear protective gloves, protective clothing and eye protection.

AS20.00-Z-0001-01A

5

Relieve pressure in coolant circuit

 In order to achieve this, turn coolant compensation tank closure cap to locking position 1.

6

Pinch off coolant outlet hose, heater (3) and coolant inlet hose, heater (4)

 Clamping device

*000589543700

7

Disconnect fuel line (7) to fuel hose (7c)

 Collect escaping fuel.

8

Detach coolant outlet hose, heater (3) and coolant inlet hose, heater (4) on STH heater unit (A6) and circulation pump (A6m1)

 Collect any escaping coolant in a clean container and feed back into the coolant expansion tank after installation is complete.

9

Undo heater unit fastener (6) from radiator support

 Bolts are fitted with large body washers.

 Support heater unit.

10

Undo heater unit fastener (6b) from cross member

 Bolts are fitted with small body washers.

 Support heater unit.

11

Lift out STH heater unit (A6) and, in doing so, detach the coupling, voltage supply (9) and coupling, control lines (10) of the electrical cables

 Pull heater unit out of installation space in direction of travel.

 

Disassemble/assemble

12

Disconnect exhaust line on STH heater unit (A6)

13

Disconnect heater-unit bracket (11) with exhaust muffler (21)

 Bracket is secured with three bolts.

 Bolt of bracket to heater unit

*BA83.70-P-1009-01A

14

Disconnect circulation pump (A6m1) from STH heater unit (A6)

AR83.70-P-5700PB

15

Install in the reverse order

16

Bleed coolant circuit after installing heater unit

AR83.70-P-5302-01E

Check

17

Check fuse assignment

 Fuse assignment of fuse box in interior compartment on driver side



Fuse assignment, as-built configuration

GF54.15-P-1256P

 Danger!

Risk of explosion caused by fuel vapors igniting, risk of poisoning caused by inhaling combustible gases and risk of injury caused by burns during and after operation of heater unit

Do not operate stationary heater, auxiliary heater or engine with heater booster in closed areas or when refueling. Allow heater unit to cool down after operation and wear protective gloves.

AS83.70-Z-0002-01A

18

Start up stationary heater

 See STAR DIAGNOSIS

If the STH heater unit (A6) switches off automatically before reaching its operating temperature and cannot be restarted again a malfunction interlock is present.

To clear fault interlock, see STAR DIAGNOSIS.



Connect STAR DIAGNOSIS and read out fault memory

AD00.00-P-2000-04A

Diagnosis system STAR DIAGNOSIS, Compact Passenger Car

*WH58.30-Z-1048-13A

19

Inspect cooling system for leaks

AR20.00-P-1010P

Number

Designation

Model
203
Thermo Top C heater

BA83.70-P-1009-01A

Screw for heater mount

Nm

10

Number

Designation

WH58.30-Z-1048-13A

STAR DIAGNOSIS diagnosis system, Compact Passenger Car

6511 1801 00