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12 90 100 Replacing Fan For Electronics Box (N73)

Necessary Preliminary Tasks: 

NOTE: Read fault memory.

Follow instructions for disconnecting and connecting battery. Refer to 12 00 ... INSTRUCTIONS FOR DISCONNECTING AND CONNECTING BATTERY .

Disconnect battery.

IMPORTANT: Follow instructions for removing and installing electronic control units.

Remove fresh air duct. Refer to 64 31 031 REMOVING AND INSTALLING/REPLACING LEFT OR RIGHT MICROFILTER AIR DUCT (AUTOMATIC A/C HIGH) .

Release screw and remove holder (1).

Release screws and remove cover (2) from control unit box.

NOTE: Release screws on seal (3) only when removing wiring harness.
Fig 1: View Of Control Unit Box Cover
G03292227Courtesy of BMW OF NORTH AMERICA, INC.

Installation: 

Insert tabs (1) in openings (2) and close cover.

Fig 2: Inserting Tabs In Openings In Cover
G03292228Courtesy of BMW OF NORTH AMERICA, INC.

1 = Integrated supply module.

2 and 3 = DME control unit.

4 = Valvetronic control unit.

5 and 6 = HDEV output stage (high-pressure fuel injector) Unlock all plug connections of control units (1-6) and disconnect.

Remove all control units (1-6).

Unlock plug connection on fan for electronics box and detach.

Release both screws on control unit carrier and remove towards top.

Fig 3: Locating Control Units
G03292229Courtesy of BMW OF NORTH AMERICA, INC.

Unfasten screws.

Remove fan (1) for electronics box.

Fig 4: Identifying Fan For Electronics Box
G03292230Courtesy of BMW OF NORTH AMERICA, INC.

Check stored fault messages.

Now clear the fault memory.