Instrument cluster (IC), networking of components - GF54.30-P-0002-06PM
The instrument cluster (A1) is connected to the Controller Area Network bus class C (engine compartment) (CAN-C) and the Controller Area Network bus class B (interior) (CAN-B). Data is exchanged with the necessary control units via CAN-C and CAN-B.
However, the instrument cluster (A1) does not serve as an interface between the CAN-C and CAN-B. This is the function of the electronic ignition switch control unit (N73).
Data from multifunction steering wheel (MFL) buttons
As the buttons of the multifunction steering wheel (MFL) (left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111)) have several functions the data from these buttons is processed as follows:
- All the buttons of the left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111) are read in by the steering column module (N80).
- The steering column module (N80) places the corresponding data on the CAN-B.
- This data is read in and evaluated by the instrument cluster (A1).
- The instrument cluster (A1) links this data with the current display in the multifunction display (A1p13) and places this data dependent on the current display as a message for the respective control units on the CAN-B.
This combination is necessary as the function of the buttons of the multifunction steering wheel (MFL) (left multifunction steering wheel button group (S110) and right multifunction steering wheel (S111)) is dependent on the current display in the multifunction display (A1p13).
On models 203.0/2 with code (428a) steering wheel shift buttons, models 203.076/276 and on model 203.7 the communication between the steering column module (N80) and multifunction steering wheel (MFL) takes place via the local interconnect network (LIN) bus. Otherwise the information is transmitted from the multifunction steering wheel (MFL) voltage-coded to the steering column module (N80).
Connections
Due to the connection of the instrument cluster (A1) to the CAN-C and CAN-B the number of connections, including the voltage supply, reduces to the following connections:
- CAN-C low
- CAN-C high
- CAN-B low
- CAN-B high
- Kl.31
- Tml. 30
- Tml. 15