AW-500E-1E, AW-500BB-4E, AW500BB-1E (Add your watch to the comments below…)
The Casio G-Shock caliber 5416 is a multi-functional analog/digital quartz movement found in the new AW-500 series revival released in October 2020.
To activate the backlight on module 5416 powered G-Shocks, press the bottom right button.
The 5416 has a modern EL backlight (aka Electroluminescent Lamp) which provides a brighter light covering the entire screen. Although an EL backlight requires less power than a traditional LCD backlight, Casio states that the battery claim of approximately 7 years only includes using the backlight for 2 seconds per day. In other words, using the backlight too many times and holding the button too long will drain your battery significantly.
Interesting note from Casio:
“The watch will emit an audible sound whenever the display is illuminated. This is caused by a transistor that vibrates when the EL panel lights up. It does not indicate malfunction of the watch.” -Operation Guide 5416