Vehicle Communications Unit (VCU)

The VCU is supplied power from the VIU through the XCVR BATT and the XCVR IGN circuit. The VCU is grounded through the XCVR DIG GND circuit to the VIU. The cellular antenna connects to the VCU. The VCU uses a three wire bus to communicate with the VIU. This three wire bus is a dedicated communication line between the VCU and the VIU. The audio commutations are made to the VCU through the VIU.