As with any light on your Mazda 6, the climate control lights will burn out over time, and in order to replace them, the cupholders must first be removed from the vehicle. The cupholders are held in by a series of clips which can be removed with a small flathead screwdriver. After the cupholders are removed, the climate control unit can be removed from the vehicle and the bulb can be replaced.
Turn off the Mazda 6's engine.
Insert the flathead screwdriver in between the top edge of the cupholder and the climate control unit. Gently pry the screwdriver upwards to remove the clip securing the cupholder into place. Repeat this process on each side of the cupholder and the side closest to the rear seats for a total of four clips.
Pull the cupholder out of the vehicle. Depending on whether your vehicle is automatic or manual, you may have to disconnect an electric plug from the bottom of the cup holder.
Uninstall the screw on the lower right hand corner of the climate control unit and the screw on the lower left hand corner with a Phillips screwdriver. Use the flathead screwdriver to remove the retaining clip above the climate control unit. Pull the unit out of the vehicle.
Pull the faulty bulb straight out of the back of the unit. Install the new bulb by pushing it in until it clicks into place. Place the unit back into the dashboard and reinstall the clip and two screws. Reinstall the cupholder and reattach all four clips and the electric plug.