Installing the left and right backrest side section

WARNING: This page is about a different car, the 2025 BMW M4, 2024 BMW M4, 2023 BMW M4, 2022 BMW M4, and 2021 BMW M4. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Description is for left component only. Procedure on the right side is identical.

Install backrest side section

Release the mounting element (1) on the detent (2) and remove from the body.
Check mounting element (1) for damage and, If necessary, replace It.
Mounting element (1) must not be damaged or missing.
Install the mounting element (1) on the backrest side section.

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Insert the bottom backrest side section (1) into the guide and position it correctly.
Clip in the backrest side section (1) on the mounting element (2).

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Disconnecting all battery ground leads
See DISCONNECTING THE NEGATIVE BATTERY CABLE OF THE SYSTEM BATTERY .

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Installing the backrest side section with the side airbag
WARNING:
Airbag unit.
Danger! Immobilization period-threatening injuries!
- Before performing any work on the airbag, always disconnect the battery ground lead from the battery.
- Airbag unit may only be set down with the cushion (airbag itself) facing upwards.
- For additional information see: SAFETY REGULATIONS FOR HANDLING COMPONENTS WITH GAS GENERATORS .
WARNING:
Pyrotechnic components.
Danger! Immobilization period-threatening injuries!
- All work on pyrotechnic parts may be carried out by technically experienced and appropriately trained personnel only.
- Replace any damaged part or ones that have been dropped.
- For additional information see: SAFETY REGULATIONS FOR HANDLING COMPONENTS WITH GAS GENERATORS .
NOTE: To provide a better overview: Schematic diagram with partially hidden components.
Insert the backrest side section (1) Into the guide at the bottom and position it correctly.
Clip in the backrest side section (1) on the mounting element (2).

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Replace screws (3).
Parts: Screws
Tighten the screws (3).
Clip in the trim (1) (arrow).
Connect connectors (4) and lock.
The connector must engage audibly.

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Activating the 48 V electrical system

Precondition

Ignition is switched off.
NOTE:
RISK OF DAMAGE
Damage to the 48-V battery
If a 48-V battery that is disconnected from the electrical system is activated, the battery electronics will be damaged.
- Only ever activate the 48 V electrical system when the 48 V battery is fully connected up.
Raise the battery ground cable (1).
Remove special tool 2 452 007 .

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Release the negative battery cable (2) of the 48-V battery from the attachment.
Position the negative battery cable (2) of the 48-V battery on the negative battery terminal.

Tighten the nut (1).

TIGHTENING TORQUE SPECIFICATIONS

Negative battery cable to 48-V battery
Nut M8	tightening torque	19 Nm

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Connect the connector (1) of the CAN bus and lock it.
Clip in the clip (2).

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Activate the 48 V electrical system by closing the hood.
The activation takes place automatically.

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NOTE: Description is for left component only. Procedure on the right side is identical.

Install backrest side section

Installing the backrest side section with the side airbag

WARNING: Airbag unit.
Danger! Immobilization period-threatening injuries!

Before performing any work on the airbag, always disconnect the battery ground lead from the battery.
Airbag unit may only be set down with the cushion (airbag itself) facing upwards.
For additional information see: SAFETY REGULATIONS FOR HANDLING COMPONENTS WITH GAS GENERATORS .

WARNING: Pyrotechnic components.
Danger! Immobilization period-threatening injuries!

All work on pyrotechnic parts may be carried out by technically experienced and appropriately trained personnel only.
Replace any damaged part or ones that have been dropped.
For additional information see: SAFETY REGULATIONS FOR HANDLING COMPONENTS WITH GAS GENERATORS .

NOTE: To provide a better overview: Schematic diagram with partially hidden components.

Insert the backrest side section (1) into the guide at the bottom and position it correctly.
Clip in the backrest side section (1) on the mounting element (2) .

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Replace screws (3) .
Parts: Screws

Tighten the screws (3) .

TIGHTENING TORQUE SPECIFICATIONS

Backrest side section with side airbag
M6x20 Replace screw.	tightening torque	8 Nm

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Clip in the trim (1) (arrow).
Connect connectors (4) and lock.
The connector must engage audibly.

Disconnecting all battery ground leads
See DISCONNECTING THE NEGATIVE BATTERY CABLE OF THE SYSTEM BATTERY .

Courtesy of BMW OF NORTH AMERICA, INC.

Activating the 48 V electrical system

Precondition
NOTE:
RISK OF DAMAGE
Damage to the 48-V battery
If a 48-V battery that is disconnected from the electrical system is activated, the battery electronics will be damaged.
- Only ever activate the 48 V electrical system when the 48 V battery is fully connected up.
Raise the battery ground cable (1) .
Remove special tool 2 452 007.

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Release the negative battery cable (2) of the 48-V battery from the attachment.
Position the negative battery cable (2) of the 48-V battery on the negative battery terminal.

Tighten the nut (1) .

TIGHTENING TORQUE SPECIFICATIONS

Negative battery cable to 48-V battery
Nut M8	tightening torque	19 Nm

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Connect the connector (1) of the CAN bus and lock it.
Clip in the clip (2) .

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Activate the 48 V electrical system by closing the hood.
The activation takes place automatically.

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