12 36 014 Removing and refitting/replacing electric motor ECU

WARNING: High-voltage system - danger to life!
The following points must be strictly observed prior to starting work :

DE-ENERGIZE THE HIGH-VOLTAGE SYSTEM
Observe SAFETY INFORMATION for working with hybrid cars.
Observe NOTES ON EARTH BONDING SCREW CONNECTIONS

IMPORTANT: Risk of damage to the EME!
Follow instructions for RAISING THE VEHICLE ON A VEHICLE HOIST .

Necessary preliminary tasks:

CLAMP OFF BATTERY LEAD FROM NEGATIVE TERMINAL
NOTE: Before disconnecting the battery cable, it must be ensured that the vehicle goes to sleep.
Remove REAR UNDERBODY PROTECTION
Open sealing cap of coolant expansion tank (high-voltage cooling circuit)

Fig 1: Overview Of Connections On Electric Motor ECU (EME)
Courtesy of BMW OF NORTH AMERICA, INC.

Overview of connections on electric motor ECU (EME):

High-voltage connection for high-voltage battery unit
Connection of equipotential bonding line
12 V grounding cable connection
Battery positive lead connection
Vent hose connection
Signal lead connection
High-voltage connection of electric A/C compressor (EKK)
Ground connection EME (on body)
High-voltage connection (transmission)
Cooling water connection, inlet
Cooling water connection, outlet

Fig 2: Locating Cover
Courtesy of BMW OF NORTH AMERICA, INC.

Unlock and disconnect high-voltage interlock loop (1).

Unlock and disconnect high-voltage plug connection (2).

IMPORTANT: Observe NOTES ON PLUG CONNECTIONS on hybrid cars.

Release nut (3) from equipotential bonding line.

IMPORTANT: Observe notes on EARTH BONDING SCREW CONNECTIONS .

Tightening torque: 12 36 4AZ .

Cut open cable strap (4).

Installation note:

Replace cable strap (4) and attach wiring to the EME.

Unlock cover (5) at the marked points and fold upwards.

NOTE: If replacing, modify cover (5) if necessary.

Release nut (6) from positive battery cable.

Tightening torque: 12 36 5AZ .

Release nut (7) from 12 V battery earth lead.

IMPORTANT: Observe notes on EARTH BONDING SCREW CONNECTIONS .

Tightening torque: 12 36 6AZ .

Installation note:

Make sure contact surfaces are clean.

Coolant emerges when coolant lines are detached.

Catch and dispose of escaping coolant.

Observe country-specific waste disposal regulations.

Fig 3: Overview Of Connections On Electric Motor ECU (EME)

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Have a container ready to catch the coolant.

Release and disconnect coolant hoses (1).

Unlock and disconnect high-voltage interlock loop (2).

Release screws (3) from high-voltage plug connection (4).

Tightening torque: 12 36 2AZ .

Detach high-voltage plug connection (4) from EME.

Unlock and disconnect high-voltage plug connection (5).

Unfasten plug connection (6) and disconnect.

IMPORTANT: Observe NOTES ON PLUG CONNECTIONS on hybrid cars.

Unclip wiring harness (7) from EME.

Unlock and detach vent hose (8).

Release bolt (1) from high-voltage cable holder.

Tightening torque: 12 36 9AZ .

Remove holder for underbody panelling (2).

Release nut (3) from grounding cable (4).

Tightening torque: 12 36 3AZ .

Detach grounding cable (4) from threaded bolt on body.

Carefully unclip high-voltage cable (5) from body.

Fig 4: Identifying Bolt, Nut, Underbody Panelling, Grounding Cable And High-Voltage Cable

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Secure EME (1) against falling out.
Check for escaping coolant remnants.

Release screws (2) from EME (1).

Tightening torque: 12 36 7AZ .

Carefully remove EME (1) toward the bottom with an assistant.

Fig 5: Identifying EME And Screws

Courtesy of BMW OF NORTH AMERICA, INC.

After installation:

Fill and BLEED cooling system.

Replacement:

Carry out VEHICLE PROGRAMMING/CODING .

Connect BMW diagnosis system:

Service functions
Power train
Hybrid car
Electrical machine electronics
Motor position sensor adjustment

Fit EME grounding cable (1) to new EME (2).

Release screw (3).

Tightening torque: 12 36 8AZ .

Installation note:

Make sure contact surfaces are clean.

Fig 6: Identifying EME Grounding Cable, EME And Screw

Courtesy of BMW OF NORTH AMERICA, INC.