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

IMPORTANT: Read and comply with notes on protection against electrostatic damage (ESD protection) . See 61 35 ... NOTES ON ESD PROTECTION (ELECTRO STATIC DISCHARGE) .

NOTE: Follow instructions for removing and installing electronic control units

Necessary preliminary tasks:

Read fault memory.
Disconnect negative battery cable . See 61 20 900 DISCONNECTING AND CONNECTING BATTERY NEGATIVE LEAD .
Remove microfilter housing . See 64 31 063 REMOVING AND INSTALLING/REPLACING RIGHT LOWER MICROFILTER HOUSING SECTION .
Remove tension strut on spring strut dome on right

Release screws (1).

Slacken nut (2).

Lift out right heater end plate (3).

Installation:

Ensure gasket (4) is correctly seated.

Fig 1: Lifting Out Right Heater End Plate

G04751296

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: Unlocking Cover Fasteners

G04751288

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

G04751298

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: Pulling Tab Out Of Housing

G04751299

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: Pulling Contact Carrier Out Of Housing

G04751300

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: Pulling Contact Carrier Out Of Housing

G04748631

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock device holder (2) at holder (1) and remove.

Remove DME control unit (3).

Fig 7: Identifying Device Holder, Holder And DME Control Unit

G04751302

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock device holder (2) at holder (1) and remove.

Fig 8: Identifying Holder And Device Holder

G04751303

Courtesy of BMW OF NORTH AMERICA, INC.

Remove device holder (1) from electronics box.

Fig 9: Identifying Device Holder

G04751304

Courtesy of BMW OF NORTH AMERICA, INC.

Release screws (1).

Replacement:

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

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

G04751305

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

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

Fig 11: Identifying Electronics Box Gasket

G04740388

Courtesy of BMW OF NORTH AMERICA, INC.