The terminal control is distributed across various control units. The following block diagram provides an overview of the control units involved and the integration in the vehicle electrical system.
MPM: |
Micro Power Module |
CAS |
Car Access System |
M-ASK |
Multi Audio System Controller |
CCC |
Car Communication Computer |
SGM |
Safety and Gateway Module |
DME/DDE |
Digital Engine / Diesel Electronics |
IBS |
Intelligent battery sensor |
|
|
K-CAN SYSTEM |
Bus system for body functions |
MOST |
Bus system in the area of audio and communication |
byteflight |
Bus system for airbag control units |
PT-CAN |
Bus system for power train and chassis functions |
There are then the following switched terminals:
Terminal 15: Controlled by the CAS depending directly on the position of the ignition key. The switch element is a semiconductor switch. Connected control units:
DSC sensor |
Sensor for Dynamic Stability Control |
PDC |
Park Distance Control (model year 03/2003) |
Note: For safety reasons, some control units have a terminal 15 line directly from CAS, e.g. the LM (light module) or the CVM (convertible top module).
Terminal 30g: Controlled by the CAS. It is switched on when the overall vehicle is woken up by an operation on the part of the user. It is switched off after a codable after-run time when terminal R is switched off. The switch element is a relay in the distribution box.
Connected control units:
AMP |
Amplifiers |
ACC |
Active cruise control |
AHL |
Adaptive Headlight |
BZM |
Centre console switch centre |
CID |
Central Information Display |
CON |
Controller |
CVM |
Convertible top module |
RAD |
Radio (only applies to satellite receivers) |
DSC |
Dynamic Stability Control |
EGS/SMG |
Gearbox control/Sequential Manual Gearbox |
EHC |
Height control |
HUD |
Head-Up Display |
KHI |
Headphones interface |
PDC |
Park Distance Control (as of model year 09/2003) |
TPM |
Tyre Pressure Monitor |
RLS |
Rain / driving light sensor |
SHD |
Slide/tilt sunroof |
SZM |
Centre console switch centre |
TEL |
Telephone |
VM |
Video module |
VTG |
Transfer Box |
Terminal 30MPM: Controlled by the MPM (Micro Power Module). Normally, terminal 30MPM is always switched on. It is disconnected when a fault status is detected in the vehicle that could lead to discharge of the battery and thus to the vehicle not starting. Input variables for this include measured values processed by the DME/DDE from the IBS (intelligent battery sensor). The switching element is a bistable relay integrated in the MPM (NB: a bistable relay is a relay that retains the switch mode even without current being applied to the coil. The application of current is only necessary for changing over.)
Connected control units:
CCC |
Car Communication Computer |
DVDC |
DVD changer |
M-ASK |
Multi Audio System Controller |
CDC |
CD changer |
NAV |
Navigation system |
Terminal 30ASE: Controlled by the SGM (Safety and Gateway Module). It is switched on when the overall vehicle is woken up. It is switched off when the vehicle goes into in the sleep mode. Terminal 30ASE is buffered by an energy reserve integrated in the SGM. This means that the power supply to the airbag control units can be bridged if the vehicle circuit power supply fails. The switch element is a semiconductor switch.
Connected control units:
SBSL |
Satellite, B-pillar left |
SBSR |
Satellite, B-pillar right |
SFZ |
Vehicle centre satellite (also has terminal 30) |
SZL |
Steering column switch cluster (also has terminal 30) |
TMBF |
Front passenger door module (also has terminal 30) |
TMFA |
Driver door module (also has terminal 30) |
Terminal 87: Controlled by the DME/DDE. It is switched on when terminal 15 is switched on and is switching off is delayed when terminal 15 is switched off. The switch element is an external relay.
Connected control units:
VTC |
Valvetronic |
Note: Terminal R is not present as a hardware terminal. The switch information is only communicated across the bus systems.