A low power sensor system and protocol are provided. Particular embodiments of the invention include a sensor controlled switch that senses conditions. While the sensor controlled switch is sensing conditions and the switch that it controls is open, power is conserved. When a valid condition is sensed, the switch is closed which enables a sensor system to receive power. The powered sensor system can then perform tasks such as listen for radio transmissions from a human interface device and respond to these. In another embodiment of the invention a delayed shutdown is executed, wherein the sensor system is put in a low power state for a period of time before responding to further conditions sensed by the sensor controlled switch. An example application is in a battery powered vehicle camera system.