BMW Heater Core Replacement

Heater Core Removal & Installation

1. Disconnect the negative battery cable. Drain coolant from the cooling system. Remove the center console.
2. Remove the mounting bolts and remove the right core mounting bracket. Lift out the front blower motor on the 7 Series.
3. Remove the core cover screws. Loosen the wire straps and clips and remove the cover.
4. Disconnect the temperature sensor(s).
5. Unscrew the mounting bolts and lift out the heater pipes. Replace the O-rings. Then, lift out the core from the right side.

To install:

1. Install the core in from the right side. Install the heater pipes with new O-rings, then tighten the mounting bolts.
2. Attach the wiring connector to the temperature sensor(s).
3. The remaining components are installed in the reverse order from which they were removed.
4. Fill the engine with the correct amount and mixture of antifreeze and water. Connect the negative battery cable, then start the engine and check for coolant leaks.

3 Series

NOTE

The heater case assembly must be removed to remove the heater core on all 3-Series vehicles.

1. Disconnect the negative battery cable.
2. Drain the cooling system into a clean container for reuse.
3. Discharge and recover the air conditioning system refrigerant.
4. Remove or disconnect the following:
   
   
   Remove the heater bulkhead from the engine compartment

   
   
   

   

   

   Fig. Heater bulkhead retaining screws

   Release hose clamps and detach the water hoses

   Release heater case screws on the firewall

   
   
   

   

   

   Fig. Heater case retaining screws

   Steering wheel and column switches

CAUTION

When removing the steering wheel on airbag equipped vehicles, use extreme caution handling the airbag assembly. Store the airbag with the airbag facing up, to avid injury in case of accidental deployment. Replace damaged airbag assemblies. Do not try to repair or reuse deployed airbag assemblies.

Center console retaining screws

All electrical leads and remove the console

Open the glove box and remove the glove box door assembly

Instrument panel trim

Left and right -A- pillar trim

Headlight switch assembly

Instrument cluster

Radio assembly and the radio trim

Ventilation control head

Passenger side airbag

Left and right defroster vents

Upper instrument panel retaining screws and pull the instrument panel away from the firewall

All electrical multi-plugs and pull the instrument panel out of the vehicle

Steering column fasteners and lower the column

Remove the fasteners from the right and left sides of the instrument panel reinforcement

Right and left head airbag assemblies if equipped

Fig. Instrument panel reinforcement side fasteners and head airbag assembly

Electrical leads from the heater

Right and left center console reinforcements

Cut the cable ties from the fusebox. Release the locks and pivot assembly downwards

Fusebox and the transverse reinforcement

Heater case retaining bolts and heater case assembly from the vehicle

Remove the core from the case assembly

To install:

1. Install or connect the following:
   
   
   Heater core into the case. Make sure the gasket is positioned properly.

   Heater case in position in the vehicle

   Fusebox and the transverse reinforcement

   Pivot fusebox assembly upwards and engage locks. Install new cable ties

   Right and left center console reinforcements

   Electrical leads from the heater

   Right and left head airbag assemblies if equipped

   Right and left side fasteners of the instrument panel reinforcement

   Raise the steering column and install new fasteners

   All instrument panel electrical multi-plugs and the instrument panel into the vehicle

   Left and right defroster vents

   Passenger side airbag

   Ventilation control head

   Radio assembly and the radio trim

   Instrument cluster

   Headlight switch assembly

   Left and right -A- pillar trim

   Instrument panel trim

   The glove box door assembly

   Center console

   Column switches and steering wheel

   Heater case screws on the firewall

   Water hoses and clamps

   The heater bulkhead in the engine compartment
2. Refill the cooling system.
3. Evacuate, charge and leak test the air conditioning system.
4. Connect the negative battery cable.
5. Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

3-Series

NOTE

The heater case assembly must be removed to remove the heater core on all 3-Series vehicles.

1. Disconnect the negative battery cable.
2. Drain the cooling system into a clean container for reuse.
3. Discharge and recover the air conditioning system refrigerant.
4. Remove or disconnect the following:
   
   CAUTION

   When removing the steering wheel on airbag equipped vehicles, use extreme caution handling the airbag assembly. Store the airbag with the airbag facing up, to avid injury in case of accidental deployment. Replace damaged airbag assemblies. Do not try to repair or reuse deployed airbag assemblies.
   
   
   
   
   Remove the heater bulkhead from the engine compartment
   
   

   

   

   Fig. Heater bulkhead retaining screws

   Release hose clamps and detach the water hoses

   Release heater case screws on the firewall
   
   

   

   

   Fig. Heater case retaining screws

   Steering wheel and column switches
   
   
   
   
   Center console retaining screws

   All electrical leads and remove the console

   Open the glove box and remove the glove box door assembly

   Instrument panel trim

   Left and right -A- pillar trim

   Headlight switch assembly

   Instrument cluster

   Radio assembly and the radio trim

   Ventilation control head

   Passenger side airbag

   Left and right defroster vents

   Upper instrument panel retaining screws and pull the instrument panel away from the firewall

   All electrical multi-plugs and pull the instrument panel out of the vehicle

   Steering column fasteners and lower the column

   Remove the fasteners from the right and left sides of the instrument panel reinforcement

   Right and left head airbag assemblies if equipped
   
   

   

   

   Fig. Instrument panel reinforcement side fasteners and head airbag assembly

   Electrical leads from the heater

   Right and left center console reinforcements

   Cut the cable ties from the fusebox. Release the locks and pivot assembly downwards

   Fusebox and the transverse reinforcement

   Heater case retaining bolts and heater case assembly from the vehicle

   Remove the core from the case assembly

To install:

1. Install or connect the following:
   
   
   Heater core into the case. Make sure the gasket is positioned properly.

   Heater case in position in the vehicle

   Fusebox and the transverse reinforcement

   Pivot fusebox assembly upwards and engage locks. Install new cable ties

   Right and left center console reinforcements

   Electrical leads from the heater

   Right and left head airbag assemblies if equipped

   Right and left side fasteners of the instrument panel reinforcement

   Raise the steering column and install new fasteners

   All instrument panel electrical multi-plugs and the instrument panel into the vehicle

   Left and right defroster vents

   Passenger side airbag

   Ventilation control head

   Radio assembly and the radio trim

   Instrument cluster

   Headlight switch assembly

   Left and right -A- pillar trim

   Instrument panel trim

   The glove box door assembly

   Center console

   Column switches and steering wheel

   Heater case screws on the firewall

   Water hoses and clamps

   The heater bulkhead in the engine compartment
2. Refill the cooling system.
3. Evacuate, charge and leak test the air conditioning system.
4. Connect the negative battery cable.
5. Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

Removal And Installation

NOTE

The heater case assembly must be removed to remove the heater core on all 3-Series vehicles.

1. Disconnect the negative battery cable.
2. Drain the cooling system into a clean container for reuse.
3. Discharge and recover the air conditioning system refrigerant.
4. If equipped with an automatic transmission, remove the screw retaining the shift lever T-handle. On manual transmission equipped vehicles, remove the shifter knob.
5. Remove or disconnect the following:
   
   CAUTION

   When removing the steering wheel on airbag equipped vehicles, use extreme caution handling the airbag assembly. Store the airbag with the airbag facing up, to avid injury in case of accidental deployment. Replace damaged airbag assemblies. Do not try to repair or reuse deployed airbag assemblies.
   
   
   
   
   Shift lever cover and pull the window switches out of the console

   Center console retaining screws, disconnect all electrical leads and remove the console

   Open the glove box and remove the glove box door assembly

   Left and right -A- pillar trim. Remove the left and right kick panel trim

   Lower instrument panel trim pads. Remove the steering wheel
   
   
   
   
   Steering column trim

   Instrument panel -A- pillar retaining bolts. Remove the lower instrument panel retaining bolts at the kick panels

   Instrument cluster retaining screws and remove the instrument cluster. Disconnect all instrument cluster electrical leads

   Radio assembly and the radio trim

   Ventilation control head

   Upper instrument panel retaining screws and pull the instrument panel away from the firewall

   All electrical multi-plugs and pull the instrument panel out of the vehicle

   Refrigerant lines from the evaporator

   Cowl cover from in the engine compartment. Disconnect the coolant lines from the heater core

   Electrical leads from the blower

   Air ducts from the heater case

   Heater case retaining bolts from the engine compartment side and the retaining bolts from the interior side

   Heater case assembly from the vehicle

   Clips retaining the case halves and remove the blower motor cover and motor

   Heater core form the case
   
   

   

   

   Fig. Exploded view of the heater/blower housing assembly-3-Series

   
   
   

   

   

   Fig.
6. Install or connect the following:
   
   
   Heater core into the case. Make sure the gasket is positioned properly.

   Assemble the case halves and attach the blower cover. Install the blower

   Heater case in position in the vehicle. Attach the air ducts

   Refrigerant lines and coolant hoses. Connect the electrical leads

   Reposition the instrument panel into the vehicle and connect the electrical multi-plugs. Be sure the instrument panel is properly positioned and install all retaining bolts

   Ventilation control head, the radio and the glove box assembly

   A pillar trim and the kick panel trim plates

   Lower instrument panel trim pieces

   Steering column trim and the steering wheel

   Center console and the shift lever cover. Install the shifter knob or handle
7. Refill the cooling system.
8. Evacuate, charge and leak test the air conditioning system.
9. Connect the negative battery cable.
10. Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

5 & 7 Series

2001-03 5 Series And 2001 7 Series

1. Disconnect the negative battery cable.
2. Drain the cooling system into a clean container for reuse.
3. Remove or disconnect the following:
   
   
   Screws retaining the center console

   Ashtray assembly

   Glove box door assembly

   Right side heater case cover screws and remove the cover

   Front vent drive motor

   Plug from the inside temperature sensor

   Heater core cover retaining screws

   Cover clips and straps

   Cover and gasket

   Coolant hoses from the heater core

   Heater pipe-to-heater core retaining bolts

   Heater pipes

   Heater core retaining bolts

   Heater core by tilting it to the side





Fig. View of the heater/blower housing assembly





Fig. Removing the heater core cover





Fig. Removing the heater water pipes





Fig. Remove the heater by pulling to the right

To install:

1. Install or connect the following:
   
   
   Heater core in the heater case

   Heater core retaining bolts

   Heater pipes to the heater core. Tighten the M6 bolts to 72-84 inch lbs. (8.1-9.5 Nm) and the M8 bolts to 16-17 ft. lbs. (21.7-23.0 Nm). Connect the heater hoses. Always use new O-rings on the heater pipes.

   Heater case cover and retaining clips

   Cover retaining screws. Make sure the cover gasket is properly positioned.

   Front vent drive motor

   Right heater case cover

   Inside temperature sensor

   Glove box door assembly

   Center console and the ashtray
2. Refill the cooling system and connect the negative battery cable.
3. Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

Except 2001-03 5 Series And 7 Series

1. Disconnect the negative battery cable.
2. Discharge and recover the air conditioning system refrigerant.
3. Drain the cooling system into a clean container for reuse.
4. Remove or disconnect the following:
5. Move the front seats completely back
6. Move steering column into the lower and extended position
   
   
   Pillar trim

   Instrument cluster

   Headlight switch

   On-board monitor assembly

   Trim panel above the pedal assembly

   Glovebox and instrument panel trim

   Center speaker connection

   Solar sensor connection

   Fasteners securing the instrument panel

   Instrument panel

   
   
   

   

   

   Fig. Remove the center speaker connector (1), instrument panel fasteners (2, 3), then pull the instrument panel (4) back

   A/C and coolant lines from the heater case

   Fasteners securing the heater case

   Heater case assembly

   Heater core cover from the case

   Coolant pipe retainers and pipes from the core

   
   
   

   

   

   Fig. Remove retainers (1) and coolant pipes (2) from the core (3)

   Heater core

To install:

1. Install or connect the following:
   
   
   Heater core in the heater case

   Coolant pipes

   Heater core cover

   Heater case assembly and fasteners

   A/C and coolant lines and fasteners

   Instrument panel and fasteners

   Solar sensor connection

   Center speaker connection

   Glovebox and instrument panel trim

   Trim panel above the pedal assembly

   On-board monitor assembly

   Headlight switch

   Instrument cluster

   Pillar trim
2. Refill the cooling system and connect the negative battery cable.
3. Recharge the A/C system with refrigerant
4. Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

5, 7 And 8-Series

Removal And Installation

1. Disconnect the negative battery cable.
2. Drain the cooling system into a clean container for reuse.
3. Remove or disconnect the following:
   
   
   Screws retaining the center console. Remove the ashtray assembly

   Glove box door assembly

   Right side heater case cover screws and remove the cover

   Front vent drive motor. Disconnect the plug from the inside temperature sensor

   Heater core cover retaining screws. Remove the cover clips and straps

   Cover and gasket. Disconnect the coolant hoses from the heater core

   Heater pipe-to-heater core retaining bolts. Remove the heater pipes

   Heater core retaining bolts. Remove the heater core by tilting it to the side
   
   

   

   

   Fig. View of the heater/blower housing assembly- 5, 7 and 8-Series

   
   
   

   

   

   Fig. Removing the heater core cover- 5, 7 and 8-Series

   
   
   

   

   

   Fig. Removing the heater water pipes- 5, 7 and 8-Series

   
   
   

   

   

   Fig. Remove the heater by pulling to the right-5, 7 and 8-Series

To install:

1. Install or connect the following:
   
   
   Heater core in the heater case. Install the heater core retaining bolts

   Heater pipes to the heater core. Tighten the M6 bolts to 72-84 inch lbs. (8.1-9.5 Nm) and the M8 bolts to 16-17 ft. lbs. (21.7-23.0 Nm). Connect the heater hoses. Always use new O-rings on the heater pipes.

   Heater case cover and retaining clips. Install the cover retaining screws. Make sure the cover gasket is properly positioned

   Front vent drive motor. Install the right heater case cover

   Inside temperature sensor. Install the glove box door assembly

   Center console and the ashtray
2. Refill the cooling system and connect the negative battery cable.
3. Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

5- & 7-Series

2001-03 5 Series & 2001 7 Series

1. Disconnect the negative battery cable.
2. Drain the cooling system into a clean container for reuse.
3. Remove or disconnect the following:
   
   
   Screws retaining the center console

   Ashtray assembly

   Glove box door assembly

   Right side heater case cover screws and remove the cover

   Front vent drive motor

   Plug from the inside temperature sensor

   Heater core cover retaining screws

   Cover clips and straps

   Cover and gasket

   Coolant hoses from the heater core

   Heater pipe-to-heater core retaining bolts

   Heater pipes

   Heater core retaining bolts

   Heater core by tilting it to the side
   
   

   

   

   Fig. View of the heater/blower housing assembly

   
   
   

   

   

   Fig. Removing the heater core cover

   
   
   

   

   

   Fig. Removing the heater water pipes

   
   
   

   

   

   Fig. Remove the heater by pulling to the right

To install:

1. Install or connect the following:
   
   
   Heater core in the heater case

   Heater core retaining bolts

   Heater pipes to the heater core. Tighten the M6 bolts to 72-84 inch lbs. (8.1-9.5 Nm) and the M8 bolts to 16-17 ft. lbs. (21.7-23.0 Nm). Connect the heater hoses. Always use new O-rings on the heater pipes.

   Heater case cover and retaining clips

   Cover retaining screws. Make sure the cover gasket is properly positioned.

   Front vent drive motor

   Right heater case cover

   Inside temperature sensor

   Glove box door assembly

   Center console and the ashtray
2. Refill the cooling system and connect the negative battery cable.
3. Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

Except 2001-03 5 Series & 2001 7 Series

1. Disconnect the negative battery cable.
2. Discharge and recover the air conditioning system refrigerant.
3. Drain the cooling system into a clean container for reuse.
4. Remove or disconnect the following:
5. Move the front seats completely back
6. Move steering column into the lower and extended position
   
   
   Pillar trim

   Instrument cluster

   Headlight switch

   On-board monitor assembly

   Trim panel above the pedal assembly

   Glovebox and instrument panel trim

   Center speaker connection

   Solar sensor connection

   Fasteners securing the instrument panel

   Instrument panel
   
   

   

   

   Fig. Remove the center speaker connector (1), instrument panel fasteners (2, 3), then pull the instrument panel (4) back

   A/C and coolant lines from the heater case

   Fasteners securing the heater case

   Heater case assembly

   Heater core cover from the case

   Coolant pipe retainers and pipes from the core
   
   

   

   

   Fig. Remove retainers (1) and coolant pipes (2) from the core (3)

   Heater core

To install:

1. Install or connect the following:
   
   
   Heater core in the heater case

   Coolant pipes

   Heater core cover

   Heater case assembly and fasteners

   A/C and coolant lines and fasteners

   Instrument panel and fasteners

   Solar sensor connection

   Center speaker connection

   Glovebox and instrument panel trim

   Trim panel above the pedal assembly

   On-board monitor assembly

   Headlight switch

   Instrument cluster

   Pillar trim
2. Refill the cooling system and connect the negative battery cable.
3. Recharge the A/C system with refrigerant
4. Operate the engine to normal operating temperatures; then, check the climate control operation and check for leaks.

E30 Models

1. Disconnect the negative battery terminal. Remove the center console and the driver's side instrument panel trim next to the steering column. Drain the coolant.
2. Loosen the coolant pipe clamp near the heater connection.
3. Remove the duct from the heater to the rear heating duct.
4. Place some rags or a small container under the heater connection to catch any spilled coolant. Remove the bolts from the heater connection and separate the joint.
5. Remove the heater core bolts and remove from the heater housing.

To install:

1. Replace the heater core into the heater housing and replace the bolts. Replace the O-rings on the heater pipe joint. Connect the pipe to the heater core and install the bolts.
2. Install the rear heating duct connection and the pipe holding clamp. Install the instrument panel trim and the center console. Fill the cooling system and bleed. Connect the negative battery terminal.

E36 3 Models

Fig. Remove the nut to disconnect the water flange-E36 3 Series

Fig. Remove the nut and the O-rings from the flange-E36 3 Series

Fig. Remove the trim screws before disconnecting the lower trim-E36 3 Series

Fig. Remove the bolt to disconnect the flange at the heater core-E36 3 Series

Fig. Remove the screw to withdraw the heater core-E36 3 Series

1. Turn the ignition switch to the OFF position. Remove the air intake cowl weather-stripping. Remove the grille by gently prying out.
2. Remove the 2 screws inside the air intake cowl holding the electrical duct.
3. Remove the 2 screws holding the right side of the air intake cowl and remove the screw holding the left side. Pull the cowl out from above. It may be very hard to remove, but it will come out.
4. Remove the nut from the heater connection and pull off the connection. Blow air into the intake hose to force the coolant out of the heater core. This will prevent coolant from dripping onto the carpeting.
5. Remove the nut from the connection in the engine compartment. Remove the screws from the left, lower instrument trim panel and pry off.
6. Remove the screw from the pipe connection at the heater core. Remove the heater core mounting nut and remove the heater core.

To install:

1. Replace the heater core and the mounting screw. Replace the O-rings on the pipe connection and install the mounting bolts.
2. Install the trim panel and screws. Install the nut on the engine compartment side of the pipe connection.
3. Replace the O-rings on the connection and install the flange and nut.
4. Install the air intake cowl and screws. Replace the electrical duct screws and the intake grill. Install the weather-stripping.