K-Bus System
The K-bus (Karosserie-bus / Body bus) connects the body electronics modules at a lower speed than the CAN-bus.
Specifications
Section titled “Specifications”- Speed: 9.6 kbit/s
- Wiring: Single wire with ground
- Protocol: BMW proprietary
Connected Modules
Section titled “Connected Modules”- General Module (GM/ZKE)
- Light Control Module (LCM)
- IHKA (climate control)
- Radio / navigation
- Multi-information display (MID)
- Rain/light sensor
- Seat module (if equipped)
Common Issues
Section titled “Common Issues”K-bus failures often manifest as intermittent operation of multiple body systems. A single failed module can disrupt the entire K-bus network.