Component Description For Steering Column Tube Module Control Unit - GF54.21-P-6051RFM
Model 205 as of model year 2019
Model 253 (except 253.99) as of model year 2020
Model 253.99
Shown with steering wheel removed
Location
The steering column tube module control unit is located directly behind the multifunction steering wheel (MFL) on the steering column tube of the steering column.
Tasks
The steering column tube module control unit has the following tasks:
- Reading in of sensors and signals
- Evaluation of input factors
- Actuation of components
- Sending signals
Reading in of sensors and signals
The input factors are read in via the following connections:
- Direct line
- Steering wheel CAN (CAN LR)
- Suspension FlexRay (Flex E)
Direct line
The signals from the following components are read via a direct line:
- Steering wheel angle sensor (N49)
- Combination switch (S4)
- DIRECT SELECT lever (S16/13)
- Steering column adjustment switch (S59) (with code 275 (Memory Package) except for code 443 (Steering wheel heater))
- Steering wheel heater and steering column adjustment switches (S59/1) (with code 275 (Memory Package) and code 443 (Steering wheel heater))
Steering wheel CAN
The steering wheel electronics (N135) directly read in the signals of the following components and transmit these via the steering wheel CAN to the steering column tube module control unit:
- Heating element temperature sensor (R22/4b1) (with CODE 443 (Steering wheel heater))
- Instrument cluster multifunction steering wheel button group (S163/1)
- Head unit multifunction steering wheel button group (S163/2)
- Steering wheel downshift button (S110/1)
- Steering wheel upshift button (S111/1)
On vehicles with code U88 (AMG steering wheel buttons (AMG DRIVE UNIT)) the lower multifunction steering wheel button group electric controller unit (A74/2) reads in the signals of the following component parts directly and sends this over the steering wheel CAN to the steering column tube module control unit:
- Lower multifunction steering wheel button group 1 (S163/3)
- Lower multifunction steering wheel button group 2 (S163/4)
Chassis FlexRay
The signal is read in from the steering column tube module control unit via the suspension FlexRay.
The functions that use these signals are described in the individual function descriptions (see the appropriate 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 wheel CAN
- Direct line
Steering wheel CAN
The steering wheel electronics directly actuate the following components; it receives the signals for this purpose via the steering wheel CAN from the steering column tube module control unit:
- Multifunction steering wheel button groups (symbol illumination)
- Steering wheel heater heating element (R22/4r1) (with CODE 443 (Steering wheel heater))
Direct line
The following component is actuated via a direct line:
- Steering wheel heater indicator lamp (S59/1e1) (with CODE 443 (Steering wheel heater))
The following components are actuated directly via a looped line by the supplemental restraint system control unit (N210):
- Driver airbag squib 1 (R12/13)
- Driver airbag squib 2 (R12/14)
Sending signals
The steering column tube module control unit sends signals over the suspension FlexRay.
On vehicles with code U88 (AMG steering wheel buttons (AMG DRIVE UNIT)) the steering column tube module control unit sends control data from the drive program control unit (N145) over the steering wheel CAN to the lower multifunction steering wheel button group electric controller unit.
The functions that use these signals are described in the individual function descriptions (see the appropriate block diagram or function schematic).
| Wiring diagram for steering column module control unit | Model 205 as of model year 2019 | PE46.10-P-2101-97FBB | |
| Model 253.99 | PE46.10-P-2101-97FCA |