LED aquarium light (a bar with many small bulbs) with manual switch built into cord; Customer requested automatic timer. Placed automatic timer between LED's plug & wall outlet. Functioned well for 2 months. Now, when the timer clicks to ON, the LED won't light fully: one end of the LED light's bar glows, but the rest is dark. BUT...
If I switch the built-into-cord switch off & on, the LED lights up! ??
If I remove the timer, the in-line switch & light function normally.
I plugged an incandescent light into the timer and the timer functions normally.