If the maintenance light turns on when you press the button, it has a few different modes/meanings:
Solid On: If the maintenance light turns on and does not blink, the ReadySet battery is fully discharged and must be charged before it will provide power for accessories.
Pattern 1 blink: If the maintenance light is blinking once with a long pause between blinks, the ReadySet has not been fully charged in some time. Charge the ReadySet using Grid/Mains charger or Solar until full and the light stops blinking. This will make the ReadySet battery last longer.
Pattern 2 blinks: If the maintenance light is blinking twice and then a long pause, the ReadySet is too warm for charging. The ReadySet will not start charging until it has cooled down to an acceptable temperature.
Notes: The ReadySet will turn to sleep mode when it is fully charged. It will not overcharge.