Disconnecting the negative battery cable of the system battery

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Preliminary work

Refer to REMOVING LUGGAGE COMPARTMENT FLOOR COVERING .

Precondition

Ignition is switched off.

WARNING: Deactivate the 12-V electrical system.
Risk of short circuits! Risk of fire!

Make sure that there is no battery charger connected to the jump start terminal in the engine compartment.
For vehicles with additional electrical systems (48 V electrical system, high-voltage vehicle electrical system), this absolutely must be deactivated before the vehicle battery is disconnected.

NOTE: TECHNICAL INFORMATION
Follow notes on lithium ion battery. See additional information NOTES REGARDING THE LITHIUM ION BATTERY (M4 2021-2023) .

Slacken nut (1).
Detach the negative battery cable (2) upwards.
Lay the negative battery cable (2) on the side and fasten it.

Courtesy of BMW OF NORTH AMERICA, INC.