(Component Description For Steering Column Tube Module Control Unit - GF54.21-P-6051GR)

Model 166 

up to Model year 2016 

Shows Model 166.0 

Courtesy of MERCEDES-BENZ USA

Location 

The steering column tube module control unit is located directly beneath the multifunction steering wheel (MFL) on the steering column tube of the steering column.

Task 

The steering column tube module control unit has the following tasks:

• Reading in of sensors and signals 
• Evaluation of input factors 
• Actuation of components 

Reading in of sensors and signals 

The input factors are read in via the following connections:

• Direct line 
• Steering LIN (LIN E1) 
• Chassis CAN 1 (CAN E1) 

Direct line 

The signals from the following components are read via direct lines:

• Steering wheel angle sensor (N49)
• Combination switch (S4)
• DIRECT SELECT lever (S16/13)
• Cruise control lever (S40/4)
• Steering column adjustment switch (S59) (except CODE 443 (Steering wheel heater))
• Steering column adjustment and steering wheel heater switch (S59/1) (with CODE 443 (Steering wheel heater))

Steering LIN 

The steering wheel electronics (N135) directly reads in the signals for the following components and sends them over the steering LIN to the steering column tube module control unit:

• Heating element temperature sensor (R22/4b1) (with CODE 443 (Steering wheel heater))
• Left multifunction steering wheel button group (S110)
• Steering wheel downshift button (S110/1)
• Right multifunction steering wheel button group (S111)
• Steering wheel upshift button (S111/1)

Chassis CAN 1 

The signals are imported by the steering column tube module control unit via the chassis CAN 1.

The functions that use these signals are described in the individual function descriptions (see block diagram or function schematic).

Evaluation of input factors 

The input factors that have been read in are evaluated by the integrated microprocessor and the relevant components are then actuated.

Actuation of components 

Components are actuated with the following lines:

• Steering LIN 
• Direct line 

Steering LIN 

The steering wheel electronics then actuates the following components directly, the signals for this are received by it through the steering LIN from the steering column tube module control unit:

• Multifunction steering wheel button groups (symbol illumination)
• Steering wheel vibration motor (M99) (with CODE 238 (Active Lane Keeping Assist) or CODE 476 (Automatic Lane Recognition))
• Steering wheel heater heating element (R22/4r1) (with CODE 443 (Steering wheel heater))

Direct line 

The following components are actuated via direct lines:

• SPEEDTRONIC LED (S40/4v1) (except CODE 494 (USA version))
• Steering wheel heater indicator lamp (S59/1e1) (with CODE 443 (Steering wheel heater))

The following components are actuated directly via looped lines by the supplemental restraint system control unit (N210):

• Driver airbag squib 1 (R12/13)
• Driver airbag squib 2 (R12/14)

Wiring diagram for steering column module control unit

PE46.10-P-2101-97NAA