61 20 900 Disconnecting and connecting battery negative lead

WARNING: High-voltage system - risk of serious injury or death.
The following points must be strictly observed prior to starting work :
Disconnect HIGH-VOLTAGE SYSTEM from power
Observe SAFETY INFORMATION for handling electric/hybrid vehicles.

WARNING: Observe SAFETY INFORMATION for handling vehicle battery.
Follow instructions for DISCONNECTING AND CONNECTING BATTERY .
Follow instructions on INTELLIGENT BATTERY SENSOR (IBS) .

Necessary preliminary tasks:

Remove COVER IN FRONT RIGHT LUGGAGE COMPARTMENT

IMPORTANT: Before disconnecting the negative lead, it must be ensured that the vehicle goes to sleep. Observe a waiting period of at least 2 minutes.

IMPORTANT: Do not under any circumstances detach or lever off intelligent battery sensor (2) from battery by force.

Loosen nut (1).

Tightening torque 61 21 1AZ .

Remove intelligent battery sensor (2) from battery and fix negative wire to side.

Fig 1: Identifying Intelligent Battery Sensor And Nut

Courtesy of BMW OF NORTH AMERICA, INC.