Steering Column Tube Module Control Unit (MRM), Component Description - GF54.21-S-6052A
Model 447
With Code XM7 (MOPF II)
The numbers on the pins indicate the pin numbering of the slots.
Steering column tube module (MRM) control unit, shown on model 447.8
Steering column tube module (MRM) control unit, shown on model 447.8
The numbers on the pins indicate the pin numbering of the slots.
The numbers on the pins indicate the pin numbering of the slots.
Steering wheel heater switch on steering column tube module (MRM) control unit, shown on model 447.8 With Code CK8 (Steering wheel heater)
Overview
This document contains information on:
- General information
- Function
- Ground connection
- Power supply
General information
The steering column tube module (MRM) control unit (N80) is installed on the driver's side in the steering column below the steering wheel.
Function
The steering column tube module (MRM) control unit (N80) records and processes all inputs made by the vehicle user on the steering wheel or steering column switches. This information is forwarded over the bus system in the vehicle to other relevant control units. If code CK8 (Steering wheel heater) is set in the vehicle, then the steering wheel heater switch (S59/1) is inserted directly at slot 4 of the steering column tube module control unit (N80).
The following input parameters and initial parameters are read in or output over direct lines by the steering column tube module (MRM) control unit (N80):
| Input parameters over a direct line | Initial parameters over a direct line |
|---|---|
| Terminal 30 | - |
| Terminal 31 | - |
| Driver's airbag squib ignition line 1 (R12/7r1) | Driver's airbag squib ignition line 1 (R12/7r1) |
| Driver's airbag squib ground connection 1 (R12/7r1) | Driver's airbag squib ground connection 1 (R12/7r1) |
| Driver's airbag squib ignition line 2 (R12/7r2) | Driver's airbag squib ignition line 2 (R12/7r2) |
| Driver's airbag squib ground connection 2 (R12/7r2) | Driver's airbag squib ground connection 2 (R12/7r2) |
| Steering wheel heater switch signal (S59/1) | - |
| - | Power supply for steering wheel heater switch (S59/1) |
| - | Steering wheel heater switch ground connection (S59/1) |
| - | Power supply for steering wheel electronics (N135) |
| - | Steering wheel electronics ground connection (N135) |
Input parameters and initial parameters for the following control units are sent or received by the steering column tube module (MRM) control unit (N80) over the steering CAN (CAN LR):
| Input parameters and initial parameters over the steering wheel CAN (CAN LR) | Additional information |
|---|---|
| Steering wheel electronics (N135) | - |
| Hand detection system control unit (N179) | - |
| Left multifunction steering wheel button group (S110) | - |
| Right multifunction steering wheel button group (S111) | - |
Input parameters and initial parameters for the following control units are sent or received by the steering column tube module (MRM) control unit (N80) over the suspension FlexRay (Flex E):
| Input parameters and initial parameters over the suspension FlexRay (Flex E) | Additional information |
|---|---|
| Electronic Stability Program (ESP) control unit (N30/4) | - |
| Electronic ignition lock (EZS) control unit (N73/8) | - |
Ground connection
"Terminal 31" ground connection is provided over the right cockpit ground point (W1/9).
Power supply
The "Terminal 30t" power supply is provided over the cockpit fuse box terminal 30/30t (F3/6).