Part 1 - Inside of Seat

Preliminary work:
Front seat removed. [1][2]Procedures
Side covering on backrest frame removed.
Rear covering on backrest removed.
Side covering on outside of seat cushion frame removed. [1][2]Procedures


Removal, Installation





1 Press off and remove trim.






2 Disconnect connector S52/2x1 and expose wire to microswitch S52/2.






3 Unscrew retainer (7) for electrical wire and remove.






4 Unscrew bracket and remove flexible drive shaft on left and right of gear drive shafts.






5 Unscrew screws on motor (M25m5) for backrest adjustment (arrows).
6 Release tension on toothed belt and remove.






7 Disconnect control cable (2) on backrest lock (4). Remove retainer and plastic washer on backrest hinge bolt, inside.






8 Unscrew bolts on inside and outside of backrest gear (8) (2 each), 12 mm Allen wrench. Observe installation note.






9 Remove backrest lock (4) with gear on backrest hinge bolt by actuating release lever on lock (arrow).






10 Remove clamping pin for holding gear spindle (diameter 3 mm).






11 Unscrew gear spindle on backrest lock (4) and remove gear (8).






12 Screw gear spindle into backrest lock until clamping pin can just be knocked in (arrow).
13 Install clamping pin (total length 30 mm).






14 Insert backrest lock (4) with gear into front seat backrest and fasten to backrest hinge bolt with plastic washer and retainer.






15 Screw in screws on gear (8) inside and outside.
Tightening torque: 35 Nm.
Observe installation note.
16 Hook in control cable (2) on backrest lock (4).






17 Adjust backrest lock by screwing in completely both gear spindles with flexible drive shaft by hand all the way up against stop.






18 Check backrest lock, both locks should lock simultaneously and completely.






19 If necessary correct adjustment of the backrest lock by slightly turning the gear drive shaft.






20 The two control cables (2 and 3) of the backrest locking system must be adjusted to a play of 0-1 mm.






21 Install toothed belt and tension by shifting motor (M25m5) upward and tighten screws.






22 Adjust tension of toothed belt to play of approx. 3 - 7 mm when force of approx. 30 N is applied by hand.






23 Install flexible drive shaft, do not change, the adjustment of the gear drive shaft set previously.






24 Engage backrest lock and check complete locking system by electrically checking the microswitches on the left and right.
Connect measuring instrument to plug board X55/3 and check both microswitches individually.

Backrest locked Nominal value: < 1 Ohm
Backrest released Nominal value: Infinity Ohms






25 Screw on retainer (7), route wire and fasten with cable straps.
Continue to reinstall in opposite order.