67 31 500 Removing and installing/replacing forward/back seat adjustment drive unit

Necessary preliminary tasks: 

• Raise front seat as far up as possible
• Procedure in event of faulty drive for forward/back seat adjustment: 

  ADDITIONAL WORK  in event of faulty drive for forward/back seat adjustment

Removing forward/back seat adjustment motor 

Unfasten plug connection (1) and disconnect.

Fig 1: Identifying Seat Adjustment Motor Plug Connection

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock retaining tabs.

Lift drive (1) with flex shaft out of guide in direction of arrow.

Pull flex shaft on left and right out of gearbox.

Fig 2: Pulling Flex Shaft Out Of Gearbox

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Installing forward/back seat adjustment motor 

Insert short flex shaft (2).

Attach rubber grommet (1).

Fig 3: Inserting Short Flex Shaft

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Installation note: 

Attach rubber grommet at 60° angle to connector housing.

Fig 4: Identifying Connector Housing Rubber Grommet Angle

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Insert long flex shaft (1) with sleeve tube (2) and rubber grommet in plastic part (3).

Fig 5: Identifying Long Flex Shaft And Sleeve Tube

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Installation note: 

Attach Unified Parts Group to motor at 60° angle to connector housing so that it cannot twist.

Fig 6: Identifying Motor Connector Housing Angle

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Slide seat rail with opening forwards or back until bushing for flex shaft mounting of worm gear is flush.

Insert flex shaft.

Fig 7: Sliding Seat Rail

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Fig 8: Identifying Adjustment Drive Short And Long Flex Shaft

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Slide short flex shaft (1) into longitudinal seat adjustment gearing square.

Bend long flex shaft (2) upwards and slide into longitudinal seat adjustment gearing.

Clip motor and flex shafts into carrier plate.

Installation note: 

PTFE hoses are shrink-fitted onto end pieces.

Check that hoses are free from damage.

Fig 9: Identifying PTFE Hoses

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Installation note: 

• Make sure flex shaft is correctly fitted on motor
• Carpet must not get between seat rails and floor panel in area of attachment points (squeaking noises)
• Powerlok screws must be replaced and must not  be reused
• Powerlok screws are mechanical screw locks with trilobular threads
• Insert all screws loose to avoid twisting
• Tighten down all screws to specified torque

Tightening torque 52 10 1AZ .

Replacement 

INITIALIZE backrest adjustment motor.

Replacing in vehicles with production dates up to 09/2009 

• Carry out VEHICLE PROGRAMMING AND ENCODING