12 90... Removing and installing/replacing electronics box

Necessary preliminary tasks: 

• Read fault memory.
• Disconnect Negative Battery Cable
• Remove both Windscreen Wiper Arms
• Remove Microfilter Housing
• Remove Cowl Panel Cover
• Remove Tension Strut On Spring Strut Dome on right

Release screws (1).

Slacken nut (2).

Lift out right end panel (3).

Installation: 

Ensure gasket (4) is correctly seated.

Fig 1: Identifying Right End Panel, Screws, Nut, Gasket And Removal Direction

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock fasteners (1) from below and slide upwards approx. 10 mm.

Unlock locks (2) in direction of arrow.

Remove cover (3).

Fig 2: Identifying Fasteners, Locks, Cover And Removal Direction

Courtesy of BMW OF NORTH AMERICA, INC.

Lift out plug connection (2), fuse carrier (3) and wiring harness grommet (4) from electronics box (1).

Installation: 

Make sure wiring harness grommets (4) are correctly seated in electronics box (1).

Fig 3: Identifying Electronics Box, Plug Connection, Fuse Carrier And Wiring Harness Grommet

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock DME control unit at holders (1) and raise slightly.

Pull tab (3) in direction of arrow out of housing and disconnect plug connections (2) on DME control unit.

Fig 4: Identifying Holders, Tab, DME Plug Connections And Removal Direction

Courtesy of BMW OF NORTH AMERICA, INC.

If necessary, press locking tabs (1) in direction of arrow and pull contact carrier (2) out of housing.

Fig 5: Identifying Contact Carrier, Locking Tabs And Removal Direction

Courtesy of BMW OF NORTH AMERICA, INC.

If necessary, press locking tab (1) in direction of arrow and pull contact carrier (2) out of housing.

Fig 6: Identifying Contact Carrier, Locking Tab And Removal Direction

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock control unit carrier (2) at holder (1) and remove.

Remove DME control unit (3).

Fig 7: Identifying Control Unit Carrier, Holder, DME Control Unit And Removal Direction

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock control unit carrier (2) at holder (1) and remove.

Fig 8: Identifying Holder And Control Unit Carrier

Courtesy of BMW OF NORTH AMERICA, INC.

Remove control unit carrier (1) from electronics box.

Fig 9: Identifying Control Unit Carrier

Courtesy of BMW OF NORTH AMERICA, INC.

Release screws (1).

Replacement: 

Modify water drain valve (2) and bump stop (3).

Fig 10: Identifying Water Drain Valve, Screws And Bump Stop

Courtesy of BMW OF NORTH AMERICA, INC.

Installation: 

Make sure gasket (1) is correctly seated on electronics box.

Fig 11: Identifying Electronics Box Gasket

Courtesy of BMW OF NORTH AMERICA, INC.