What must be true for a center high-mount stop lamp (CHMSL) on a truck with a camper?

For a center high-mount stop lamp (CHMSL) on a truck equipped with a camper, it is essential that the lamp is operational if the camper has its own CHMSL. This requirement exists because the CHMSL enhances visibility for following vehicles, making it clear when the vehicle is stopping. If the camper is fitted with its own CHMSL, the original CHMSL of the truck remains important for safety reasons and legal compliance.

The operation of the CHMSL is critical for promoting safety, especially in conditions where visibility may be reduced. Having both lights operational maximizes the chances that drivers behind the vehicle will notice the brake lights and react accordingly. While there may be variations in the regulations governing equipment based on age or manufacturing details, the primary focus remains on the functionality of safety features, such as stop lamps.