52 13 385 Replacing gas cartridge (pyroactivator) for crash-active head restraint on front seat

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2010 BMW 535xi, 2010 BMW 535i, 2009 BMW 535xi, 2009 BMW 535i, and 2008 BMW 535xi. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Read and comply with SAFETY REGULATIONS for handling airbag modules and pyrotechnical belt pretensioners.
Incorrect handling may result in triggering of the crashactive head restraint and thereby cause injury.

Switch off ignition!

Necessary preliminary tasks:

Disconnect BATTERY NEGATIVE LEAD
Remove crash-active head restraint. See REMOVING AND INSTALLING/REPLACING FRONT LEFT OR RIGHT CRASH-ACTIVE HEAD RESTRAINT or REMOVING AND INSTALLING/REPLACING FRONT LEFT OR RIGHT CRASH-ACTIVE HEAD RESTRAINT

IMPORTANT: The pyrotechnical device may be replaced up to 5 times.
Triggering frequency is denoted on the sticker on the head restraint carrier.
Stickers are available as spare parts.

Starting situation:

Head restraint is in the crash position after being triggered.

NOTE: Pyroactivator can only be removed in the triggered state.
The complete crash-active head restraint must be replaced if the event of a head restraint fault signal and an untriggered pyroactivator.

Fig 1: Identifying Head Restraint In Crash Position

Courtesy of BMW OF NORTH AMERICA, INC.

Removing cover:

Raise cover (1) and pull towards rear.

Fig 2: Removing Cover

Courtesy of BMW OF NORTH AMERICA, INC.

Removing pyrotechnical device:

Press together retainer (1) for pyrotechnical device at lugs.

Feed out pyrotechnical device.

Fig 3: Pressing Retainer For Pyrotechnical Device

Courtesy of BMW OF NORTH AMERICA, INC.

Removing pyroactivator:

Pull pyroactivator (2) out of mounting (1) for pyrotechnical device.

Unlock PLUG CONNECTION (3) and disconnect.

IMPORTANT: Dispose of plastic element and pyroactivator.

Fig 4: Identifying Pyroactivator, Mounting And Plug Connection

Courtesy of BMW OF NORTH AMERICA, INC.

Procedure for installing pyrotechnical device:

Bringing head restraint together - version without button (MFS):

Pull spring catches apart and push head restraint together.

Maintain position.

Fig 5: Pulling Spring Catches

Courtesy of BMW OF NORTH AMERICA, INC.

Bringing head restraint together - version with button (Basic):

Press button (1) and push head restraint together.

Maintain position.

Fig 6: Pushing Head Restraint

Courtesy of BMW OF NORTH AMERICA, INC.

Locking release plate:

Hold pushed-together head restraint in position and push release plate (1) upwards up to stop.

Release plate (1) must audibly snap into place.

Fig 7: Pushing Release Plate

Courtesy of BMW OF NORTH AMERICA, INC.

Checking head restraint lock:

Check end position of release plate (1).

All four springs must be engaged (snapped into place).

Fig 8: Locating End Position Of Release Plate

Courtesy of BMW OF NORTH AMERICA, INC.

Replacing pyrotechnical device:

Connect plug (1) to new pyroactivator (2) and LOCK .

Clip pyroactivator (2) into new mounting (3).

Fig 9: Identifying Plug, Pyroactivator And Mounting

Courtesy of BMW OF NORTH AMERICA, INC.

Installing pyrotechnical device:

Press together retainer for pyrotechnical device at lugs.

Insert retainer for pyrotechnical device into release plate and tilt in upward direction.

Retainer for pyrotechnical device must audibly snap into place.

NOTE: Check seating of retaining lugs in retainer.

Fig 10: Pressing Retainer For Pyrotechnical Device

Courtesy of BMW OF NORTH AMERICA, INC.

Laying wiring harness:

Secure wiring harness in carrier section with strain relief.

Fig 11: Identifying Wiring Harness In Carrier Section With Strain Relief

Courtesy of BMW OF NORTH AMERICA, INC.

Mounting cover:

Clip cover onto carrier section.

Cover must audibly snap into place.

Fig 12: Identifying Clip Cover Onto Carrier Section

Courtesy of BMW OF NORTH AMERICA, INC.