Theory Of Operation
The DSM receives fused B+ from the Power Distribution Center (PDC) and is supplied by a ground eyelet secured to the floor pan, to the right of the floor console. In addition, the DSM status is broadcast over the Controller Area Network - Interior High Speed (CAN-IHS) data bus to be used by the radio when the radio sends a CAN message for the status of the DSM.
The radio receives touchscreen signals via the LVDS wire harness that connects directly between the radio and DSM. The DSM communicates via a hardwired back-channel protocol with the radio over the LVDS wire harness.
The DSM provides all of the functions of the radio with integral touchscreen. Unlike a radio with integral touchscreen, the DSM is disassociated from the radio and connected by a LVDS wire harness.
The DSM receives vehicle configuration and network configuration information from the vehicle configuration management system via the CAN-IHS data bus. Any diagnostic or loss of communication states are also sent via the CAN-IHS data bus.