I need to change turn signal combination switch.

Remove/Install
1 Disconnect ground cable of battery
CAUTION: To protect against unwanted contact between the disconnected ground line and the ground (right major assemblies compartment, common ground W16/4, insulate cable lug of ground line.

2 Remove steering wheel
CAUTION: when handling airbag unit improper handling can lead to damage to the airbag unit.

3 Remove clock spring contact
4 Unscrew screws (1) and remove lower steering column molding (2)
5 Remove upper steering column molding (3)
6 Remove covers (12) on left and right
7 Disconnect electrical connectors at the covers (12)
NOTE: Only with left/right folding outside mirror, code 500 and headlamp cleaning system, code 600.

8 Unscrew screw (4) and disconnect connector (9)
9 Unscrew screw (8) and remove cruise control switch (S40)
10 Unscrew screws (5)
11 Pull combination switch (S4) off the retaining webs (6) and remove
12 Install in the reverse order
13 Perform function check