A multifunction sensor device which provides various transducer functions including means for performing temperature sensing, ambient light sensing, motion detection, switching functions and a means to put the device in an on, off or auto mode. The device has utility in environments such as that found in offices, schools, homes, industrial plants or any other type of automated facility in which sensors are utilized for energy monitoring and control, end user convenience or HVAC control. Key elements of the invention include overcoming the difficulty of mounting diverse sensors or transducers within the same device or housing; permitting these various sensors to exist in a single package that can be mounted to a wall in a substantially flush manner; and eliminating the requirement of an air flow channel in the device, thus minimizing any adverse effects on the motion detecting element or sensor as well as providing built in partial hysteresis. The device may include additional transducers or sensors and is constructed such that the temperature sensor is neither exposed to the flow of air in a room or area nor in an airflow channel whereby a chimney effect may occur. The device has a passive alcove or cavity that acclimates to the ambient air temperature through the process of diffusion. The device can transmit and receive real time data, relative data and actual discrete data in addition to switching and controlling loads locally or remotely.