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12 90... Removing and installing/replacing electronics box (N57)

IMPORTANT: Read and comply with notes on protection against electrostatic damage (ESD protection). Refer to NOTES ON PROTECTION AGAINST ELECTROSTATIC DAMAGE .
NOTE: Follow INSTRUCTIONS for removing and installing control units!

Necessary preliminary tasks: 

Slacken nut (1).

Release screw (2).

Remove heat shield (3).

Fig 1: Identifying Heat Shield, Screw And Slacken Nut
G08469786Courtesy of BMW OF NORTH AMERICA, INC.

Release screw (1).

Lay filler neck (2) for windscreen washer fluid to one side.

Fig 2: Identifying Filler Neck And Screw
G06888958Courtesy of BMW OF NORTH AMERICA, INC.

Release screws (1).

Tightening torque 12 90 2AZ .

Remove electronics box cover (2).

Fig 3: Identifying Electronics Box Cover And Screws
G06888959Courtesy of BMW OF NORTH AMERICA, INC.

Unlock all plugs (1) from control unit and detach.

Unclip grommet hold-down device (2) and remove.

Detach rubber grommets (3) from electronics box. Place wiring harnesses to the side.

Installation note: 

Make sure grommets are correctly fitted (watertightness).

Fig 4: Identifying Rubber Grommets, Grommet Hold-Down Device And Connectors
G06888960Courtesy of BMW OF NORTH AMERICA, INC.

N54 only: 

Unlock plug (1) from electronics box fan and pull off.

Fig 5: Identifying Plug At Electronics Box
G09914059Courtesy of BMW OF NORTH AMERICA, INC.

Release screws (1).

Tightening torque 12 90 1AZ .

Pull off air duct (2) from the electronics box.

Feed electronics box (3) out upward and remove.

Installation note: 

When replacing electronics box, modify DME or DDE CONTROL UNIT .

Fig 6: Pulling Off Air Duct From Electronics Box
G09914060Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

When installing the electronics box, insert guide (1) on engine support.

Fig 7: Identifying Guide On Engine Support
G06888950Courtesy of BMW OF NORTH AMERICA, INC.