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Home >> BMW >> 2012 >> M3 2D Convertible, Standard Trans >> Repair and Diagnosis >> Engine Performance >> Ignition System >> Engine Electrical System - Repair -- M3 Convertible >> Control Unit Box >> 12 90... Removing and installing/replacing electronics box
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12 90... Removing and installing/replacing electronics box

IMPORTANT: Read and comply with notes on PROTECTION AGAINST ELECTROSTATIC DISCHARGE (ESD PROTECTION) .
NOTE: Follow instructions for REMOVING AND INSTALLING ELECTRONIC CONTROL UNITS 

Necessary preliminary tasks: 

Release screws (1).

Slacken nut (2).

Lift out right heater end panel (3).

Installation note: 

Ensure gasket (4) is correctly seated.

Fig 1: Lifting Out Right Heater End Plate
G04751296Courtesy 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: Removing Cover Fasteners
G04751288Courtesy of BMW OF NORTH AMERICA, INC.

Release plug connection (2), fuse carrier (3) and wiring harness grommet (4) from electronics box (1) in upward direction.

Installation note: 

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

Fig 3: Identifying Wiring Harness Grommets, Electronics Box, Plug Connection And Fuse Carrier
G04751298Courtesy of BMW OF NORTH AMERICA, INC.

Unlock DME control unit from holder (1) and raise slightly.

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

Fig 4: Removing DME Control Unit From Holder
G04751299Courtesy 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: Pressing Locking Tabs
G04751300Courtesy 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
G04748631Courtesy of BMW OF NORTH AMERICA, INC.

Unlock equipment holder (2) on holder (1) and remove.

Remove DME control unit (3).

Fig 7: Removing DME Control Unit
G04751302Courtesy of BMW OF NORTH AMERICA, INC.

Unlock equipment holder (2) on holder (1) and remove.

Fig 8: Identifying Equipment Holder On Holder
G04751303Courtesy of BMW OF NORTH AMERICA, INC.

Remove equipment holder (1) from electronics box.

Fig 9: Identifying Equipment Holder On Electronics Box
G04751304Courtesy 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 And Bump Stop
G04751305Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

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

Fig 11: Identifying Electronics Box
G04740388Courtesy of BMW OF NORTH AMERICA, INC.