Steering column tube module control unit, component description - GF54.21-P-6051FQ

MODEL 218 

Location 

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

Task 

The steering column tube module control unit is used for exchanging data between the multifunction steering wheel controls and the corresponding control units.

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 (CAN E) 

Direct line 

The signals from the following components are read via a direct line:

• Steering angle sensor (N49)
• Combination switch (S4):
  • Turn signal lamps switch (S4s1)
  • Headlamp flasher and high beams switch (S4s2)
  • Low beam switch (S4s3)
  • Windshield washer system switch (S4s4)
  • Wipe switch (S4s5)
• DIRECT SELECT lever (S16/13)
• CRUISE CONTROL lever (S40/4):
  • Resume from memory switch (S40/4s1)
  • Decelerate and set switch (S40/4s2)
  • Accelerate and set switch (S40/4s3)
  • OFF switch (S40/4s4)
  • Indicator switch (S40/4s5)
  • SPEEDTRONIC switch (S40/4s6) (without code (494) USA version and without code (498) Japan version)
  • DISTRONIC control (S40/4r1) (with code (233) DISTRONIC PLUS)
• Steering column adjustment switch (S59) (without 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)
• Downshift steering wheel gearshift button (S110/1)
• Right multifunction steering wheel button group (S111)
• Upshift steering wheel gearshift button (S111/1)

Chassis CAN 

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

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 affected components are then actuated.

Actuation of components 

The actuation of the components takes place via the following connections:

• Direct line 
• Steering LIN 

Direct line 

The following components are actuated via direct lines:

• SPEEDTRONIC LED (S40/4v1) (without code (494) USA version and without code (498) Japan version)
• Steering wheel heater indicator lamp (S59/1e1)

  (with code (443) Steering wheel heater)

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:

• Symbol illumination of the multifunction steering wheel button groups
• Steering wheel vibration motor (M99)

  (with code (476) Automatic lane detection)

The following components are actuated directly through a looped line by the Supplemental Restraint System control unit (N2/10):

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

On vehicles up to 31.5.12, the following component is actuated via a looped line directly by the steering wheel heater control unit (N25/7)

(with code (443) Steering wheel heater):

• Steering wheel heater heating element (R22/4r1)

Wiring diagram for steering column module control unit

PE46.10-P-2101-97XAA