Brief component description
Main buses are responsible for the inter-system data exchange between the control units. This also includes the system functions diagnosis, programming and encoding.
Sub-bus systems exchange data within a function group. For example, if the data of the intelligent battery sensor or the preheating control unit from the engine control (DME or Digital Diesel Electronics) is read in.
Example, engine control (DME or DDE)
| Item | Explanation |
|---|---|
| 1 | Active air-flap control |
| 2 | Intelligent battery sensor |
| 3 | Preheating control unit |
| 4 | Coolant pump for charge air cooler |
| 5 | Engine control |
Further examples are:
- Connection of the footwell module to the switch block of the driver's door and the exterior mirror
- Connection of the roof function center to the rain-light-solar-condensation sensor
- Connection of the Automatic air conditioning the 15 servomotors
Example, footwell module (FRM)
| Item | Explanation |
|---|---|
| 1 | Operating facility for light |
| 2 | Driver assist systems control panel |
| 3 | Exterior mirror, driver's side |
| 4 | Exterior mirror, passenger's side |
| 5 | Seat adjustment switch block, driver's side |
| 6 | Seat adjustment switch block, passenger's side |
| 7 | Driver's door switch block |
| 8 | Headlight driver module, left |
| 9 | Headlight driver module, right |
| 10 | Footwell module (FRM) |
In a LIN bus system, there is always only one master control unit installed. A maximum of up to 16 users (so-called slaves) may be connected. There is no prescribed bus structure. The maximum cable length for a LIN bus is limited to 40 meters. The data transfer rate of the LIN spans from 2.4 to 19.2 kBit/s. A closing termination is not absolutely necessary due to the lower data transfer rate.