Assuming your lights have an established history of good performance, the reason your solar garden lights have stopped working is probably because of charge issues – meaning they are not receiving adequate sunlight or they are not storing enough electricity.
A good way to troubleshoot this would be to move your light to a new area where you are confident that it is receiving a good dose of unobstructed sunshine.
If your garden light performs as expected, then it would be fair to assume that there is a charging issue – either the solar cell is degrading or something is preventing adequate sunshine from striking it (outdoor shrubbery may have grown more than you realize).
However, if your light performs, but only for a very short while, this could point to a battery that has neared the end of its life.
Batteries are rated in cycles (one discharge and recharge being a cycle). As the battery gets near the end of its cycles, it will hold less and less of a charge. This would result in degraded performance.
New Garden Lights Not Working
Arguably, the most common reason for new solar garden lights not working is because they haven’t been turned on.
Outdoor garden lights generally come with an on/off switch. Manufacturers do this in order to keep the lights from engaging when the lights are in storage.
As mentioned above, batteries work in cycles. And if your light found itself in a dark place, such as a enclosed box, then it would attempt to illuminate the dark area – burning through battery capacity.
Further complicating things is the fact that some batteries can actually be damaged when the charge drops too low.
By turning your light off, the manufacturer prevents any unwanted use of the light and, more importantly, any excessive discharge of the battery.
# Note #
For an in-depth look at this, please read, ‘Do You Need To Turn Solar Lights Off?’
Garden Lights: Signs Of Aging
Despite having no moving parts, solar garden lights do wear down. You may find that your light does not shine as brightly as it has in the past. This may be due to battery fatigue or because of encroaching leaves.
It is also possible that your solar cell is dropping in performance because of age, however this is unlikely. Generally speaking, quality solar cells will still be performing at 90% capacity, even after several years.
Garden Lights Need Cleaned
The outdoor world has a plethora of things that can add up to degrade your lights’ performance. Dust and pollen can cover your solar cell and reduce the amount of sunlight that comes in contact with it – lowering its capacity to charge.
And even if the solar cell that powers your light is clean, it may be that the glass/plastic that holds the L.E.D. lighting your outdoors is covered in dust.
Pathway lights in particular are prone to this as every time the lawn is mowed, dust is being blown around, especially at ground level.
As a number of outdoor solar lights contain plastic parts, this makes them subject to bad weather. Excessive heat, cold, rain and hail will definitely wear on the outer shell of your light.
And if moisture collects on the inside of your light, possibly due to a seal that has broken because of the elements, this can have devastating effects on the electrical components of your light.
Batteries in particular can find themselves covered in corrosion and this will eventually prevent the light from performing.