Electrical System
The demands on modern cars are continually increasing. Buyers expect an ever growing array of functions, while legal requirements relating to fuel consumption and emission levels are becoming stricter all the time. Such demands can only be met by the increased use of electronic components and intelligent interaction between them.
Conventional electrical system are no longer capable of handling the ever growing volume of data in modern cars. In order to be able to process all information in real time, substantially faster communication channels are required.
That is why new data bus systems have been introduced on the E65. Two of them are based on fiber-optic technology. The "Media Oriented System Transport" (MOST) system for multimedia applications (data transfer rate: 22.5 MBd) and the "byteflight" safety systems bus (10 MBd).
The body Controller Area Network (K-CAN, 100kBd) on the E65 consists of two copper twist wires and replaces the previous K-Bus (9.6 kBd).
The PT-CAN (500 kBd) for the powertrain related control units has been expanded to a 3-wire interface.
The power supply to all electric components is controlled by the " Power Module". This is a new development for the E65 which ensures that the charge level of the battery is maintained both when the engine in running and when it isn't and even in the event of faults in the electrical system. If necessary, the Power Module switches to "emergency mode" in order to ensure that essential systems remain functional while driving.
For the first time, a lightweight aluminum ribbon cable is used for the positive lead. The high current plug in contacts are also a new feature and can withstand peak currents of up to 220 A, with a continuous load rating of 100 A: despite such high current ratings, these contacts are crimped not soldered.
If no electrical functions are operated for a continuous period of three weeks, the E65 battery is automatically isolated from the electrical system. This ensures that the battery is adequately protected against power drain. An additional data memory that can be accessed using the Diagnostic program provides a status read-out of the battery load and life.