52 14 899 Additional work (normal/ electric) with defective drive for longitudinal adjustment

Set seat tilt adjustment to max. up setting.

Release screw (1) on actuator drive (2) of longitudinal seat adjustment.

Fig 1: Releasing Screw On Actuator Drive Of Longitudinal Seat Adjustment

Courtesy of BMW OF NORTH AMERICA, INC.

Release screw (1) on servodrive (2) of longitudinal seat adjustment and remove servodrive (2).

Fig 2: Removing Servodrive

Courtesy of BMW OF NORTH AMERICA, INC.

Activate the operating switch for the seat position adjustment:

1. No function:
   • Disconnect plug for longitudinal seat adjustment
   • Connect new servodrive and check function
   • If servodrive is running, gear is O.K.
   • Reassemble front seat
2. Actuator drive running:
   • Transmission for longitudinal seat adjustment defective!
   • Continue with

Disassembly of faulty gear for longitudinal seat adjustment

Disassembly of faulty gear (1) for longitudinal seat adjustment: 

(2) Input shaft

(3) Internal gear

Fig 3: Identifying Gear, Input Shaft And Internal Gear

Courtesy of BMW OF NORTH AMERICA, INC.

Using a pneumatic saw (1),

cut through drive shaft (2) from rear.

Fig 4: Cutting Drive Shaft From Rear

Courtesy of BMW OF NORTH AMERICA, INC.

Remove drive shaft (1) from gear (2).

Fig 5: Removing Drive Shaft From Gear

Courtesy of BMW OF NORTH AMERICA, INC.

Release screw (1) and remove gear (2).

Fig 6: Releasing Screw And Removing Gear

Courtesy of BMW OF NORTH AMERICA, INC.

Over rest of drive shaft (1), adjust front seat, release screws on floor panel and remove front seat, refer to 52 14 000 REMOVING AND INSTALLING LEFT OR RIGHT FRONT SEAT (NORMAL/ELECTRIC)  .

Fig 7: Removing Gear

Courtesy of BMW OF NORTH AMERICA, INC.

Replace seat mechanism on front seat.