EMERGENCY CENTER HIGH MOUNTED STOP LAMP (CHMSL) CONTROLLER

An improved Center High Mounted Stop Lamp (CHMSL) harvests electrical power while providing additional features when the CHMSL is not powered during a brake application. Electronic circuitry determines if the different sources of electrical power have sufficient energy to activate the light-emitting device; senses a vehicle braking or emergency event to activate the light-emitting device upon sensing the event; and switches from one source of electrical power to a different source of electrical power if it is determined that a particular source of electrical power has become depleted or incapable of activating the light-emitting device. The different sources of electrical power may include a supercapacitor, a rechargeable battery, or a primary battery. The electronic circuitry operative to sense a braking or emergency event may include a brake signal input or an inertial measurement unit (IMU).