A control system (300) for a transport engineless refrigeration unit (301), the control system including: a controller (302) for communication between a vehicle (307) and a plurality of vehicle devices, the controller comprising: a vehicle data connection (306) for transmitting data to and from a vehicle; a vehicle engine on/off connection (308) for triggering start-up of the vehicle engine; a plurality of device data connections (314), each device data connection transmits data to and from at least one device external to the controller; and a device power connection (313), the device power connection supplies power from the controller to at least one device external to the controller.