Sunroof Description and Operation (C3U): Notes
The sunroof is a Bottom Loaded top-Slide type sunroof system. The sunroof contains moving glass panel, a moving front sunshade and a moving rear sunshade. Moving Glass is controller by Glass Motor Controller. Front shade and rear sunshade is controlled by Master Motor Controller.
The electrical portion of the tilt/slide sunroof system consists of:
- Body control module (BCM)
- Sunroof glass control module
- Sunroof control switch assembly
- Vent control switch assembly
- Serial Data Bus
- Sunshade control switch
- Rear Sunshade control switch
The sunroof electrical system uses a master/slave configuration utilizing a serial data based system for communication. The BCM is designated as the master, while the sunroof control module is configured as the slave.
As the system master, the BCM uses the serial data communication bus to enable or disable sunroof operation, communicate vehicle information to the sunroof controller, and request sunroof movement. The sunroof controller provides system status and diagnostic information to the BCM for diagnostic reporting and operational purposes.
The sunroof glass is controlled by a integrated motor/controller containing the necessary electronics, motor, hall effect position sensors, as well as the interface to the driver control switches. The motor/controller is capable of controlling motion based on control switch activation and serial data message commands from the system master.
The operational calibrations for the sunroof integrated motor/controller are loaded over the serial data communication bus by the sunroof system master, the BCM.