Thermally activated power supply for sensor system

This invention generally relates to a temperature-based sensor for detecting undesirable vibrations or temperatures in a vehicle component. A sensor system includes a housing that houses a thermally sensitive sensor, a transmitter portion and a power source. Preferably, the sensor device is encapsulated to protect the components from the environment. The transmitter generates a signal in response to the sensor detecting a temperature in a vehicle component that exceeds a predetermined temperature. A receiver is located remotely from the transmitter to receive the signal. The power supply generates electricity when the temperature of the vehicle component achieves an initial threshold temperature that is less than the predetermined temperature.