A cap lamp system features a battery pack, a cap lamp housing containing a cap lamp bulb and a power cord connected between the battery pack and the cap lamp housing. The power cord provides power to the cap lamp bulb from the battery pack. An electronic module includes a housing defining a chamber and electronic circuitry is positioned within the chamber of the housing. The electronic module is positioned in circuit with the power cord. The electronic module may receives power from the battery pack and the electronic circuitry of the electronic module may includes a battery that powers the module.