LED Lights glow dimly when plugged in
I have a couple strings of LED lights (I think they are the C7 or C9 type globes on them) that I had used on a timer for a couple hours each evening that were on a timer. Over the last couple months, I noticed that the light output was getting dimmer and dimmer, until finally they appeared to be out.
However, when I was able to take them down & start going through the string, things looked like they were okay. I plugged the string into an outlet & found that they were not out - just very very dim. I had to be in pitch dark to see them glow to any degree.
The fuses in the plug appeared to be intact & I know I'm getting good, grounded AC power out of the outlet I am plugging them in to. Since the fuses appear to be intact, I'm at a loss as to what the actual issue is. Both strings of lights seem to be similarly affected. I have ruled out that the timer is the issue, since it's no longer in the equation. I am plugging these lights straight into a grounded outlet that gives me strong 116-120 volts out of it.
Do the LED lights in these strings just "give out" after so many hours? I was hoping that, as expensive as these strings can be, that they'd be a little more hearty.
Is there a way to determine what is going bad with these lights? I would appreciate any suggestions.