Bus Systems

Bus systems

Bus systems enable the individual control units on the vehicle to be networked with one another via "serial interfaces." The use of bus systems in vehicle electrical systems provides a number of advantages.

Advantages of Bus Systems

- Greater reliability of the overall system
- Simplification of wiring systems
- Reduction of the number of separate cables
- Reduction of the cross-sectional areas of wiring looms
- Greater versatility in terms of cable routing
- Multiple use of sensors in the vehicle, thereby reducing the number of duplicated sensors
- Use of shared interfaces by signals, thereby reducing the number of interfaces
- Transmission of complex data
- Greater flexibility in the event of system modifications
- Data volume can be expanded at any time
- Flexible configuration of control units
- Adoption of new functions for customers
- Efficient diagnosis
- Lower hardware costs

The E65/E66 introduces three (3) new bus systems. Two of them are based on fiber-optic technology. The two new fiber-optic bus systems are called:

MOST bus (Media Orientated System Transport) and "byteflight" (safety systems bus).

The third bus system consists of two insulated copper twisted-pair wires and is called the:

K-CAN (Body-Controller Area Network). The K-CAN bus replaces the single wire K bus (body bus) and is subdivided into two sections: the K-CAN System and the K-CAN Periphery.

The powertrain control units continue to use a CAN bus called the PT-CAN, except that now it is a three wire bus to include a KL-15 wake-up wire.

Comparison of E38 and E65/E66 bus systems

Comparison Of E38 And E65 Bus Systems:

Bus Communication Speeds

The communication speed of the busses in the E65/E66 have been increased significantly to handle the demand placed on them by a greater number of control units.

Here is a comparison between the busses of the E38 and the E65/E66.