I have an old, broken, cheap LED bulb. It broke some time ago. I’ve diagnosed what was wrong with it but never actually repaired it, until today.
Popping open the diffuser was easy. Inside the problem was immediately clear. The electrolytic capacitor had exploded. Other than that one of the LED was open circuit. I tested all the LEDs using my multitester and everyone lit up except the broken one. The 0.82μF 400V polyester film capacitor on the back seemed OK.
I had desoldered the electrolytic capacitor some time ago. Today I desoldered the LED and that was difficult. This broken SMD LED’s plastic body easily melt when touched by my soldering iron tip.
After soldering the replacement LED and electrolytic capacitor I tested it using the mains current limiting rig but not the way I intended to when I built that rig, as in this time I don’t use it to limit current. After initial test without diffuser went fine, I popped the diffuser back on, retested it and everything still went OK.
Just like that this cheap old LED bulb can be used again.
See you later folks!