Samsung SL202 Flashing Yellow Light

The Rii i8 is a wireless keyboard with a built-in touchpad and backlit keys. The yellow flashing light on the Rii i8 keyboard indicates that the battery is low and needs to be charged.
When the battery is low, the yellow light will start flashing, indicating that the keyboard is in low-power mode. To charge the keyboard, plug it into a USB port using the included charging cable. The yellow light will turn off once the battery is fully charged.
It's important to keep the keyboard charged to ensure that it functions properly. If the battery is too low, the keyboard may stop working or the keys may become unresponsive. It's a good idea to charge the keyboard overnight or when it's not in use to ensure that the battery is fully charged when you need to use it.

According to the owners manual for these swimming pool lights, this is what each colored indicator means. Hope this helps.


Solid green
The battery pack is fully charged.
Slow flashing green
The battery pack is almost fully charged.
Slow flashing yellow
The battery pack is half charged.
Medium flashing yellow
The battery pack is less than half charged.
Fast flashing yellow
The battery pack has almost no charge.
Fast flashing red
A charging error has occurred and the light should be unplugged and then plugged back in. If the Fast Flashing Red persists after several attempts, the battery condition is questionable.



Also in the trouble shooting guide, it mentions this:


Problem: Red Indicator Light Is Flashing While Charging

Solution:
A red flashing indicator light when charging indicates a selftest
error condition. Unplug the product and plug it in again.
Try this several times; if the indicator light continues to flash
red, unplug the GlowBuoy and take it to an authorized service
depot.

You may have to replace the rechargeable lithium ion battery. (Even rechargeable batteries have a life-span :)