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.

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

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 OK.
   • Reassemble front seat
2. Actuator drive running:
   • Transmission for longitudinal seat adjustment defective!
   • Continue with

     Disassembly of faulty gear for longitudinal seat adjustment

   Fig 2: Removing Servodrive

   Courtesy of BMW OF NORTH AMERICA, INC.

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

(2) Input shaft

(3) Internal gear

Using a pneumatic saw (1), cut through drive shaft (2) from rear.

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

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

Over rest of drive shaft (1), adjust front seat, release screws on floor panel and remove front seat.

Replace seat mechanism on front seat.