Cheap, Chinese, and not working. This is one of the few situations where two out of three is better than ain't bad. I order these from Ali Express for a couple dollars. I knew something could be done creepily seeing that some would fail only a few months after getting them. most of them are assembled with inexpensive easily obtained components.
Step 1: Assess the Situation.
First, remove the diffuser lens cap. Most of them screw off, but this one pops off like an Easter egg. Using a standard digital multimeter set to diode, and paying attention to polarity, I check each LED for light. If one doesn't light up, double check polarity, of it still doesn't light up then mark it with a Sharpie for removal.
Step 2: Removal.
The LED is easily removed using a small blade to apply gentle prying pressure, and soldering iron tip. You w will likely see almost no thermal paste, which lead to the LED failing in the first place. don't forget to dab some thermal paste on the heat sink.
Step 3: Installation Is Reverse of the Removal.
Your heat sink still has enough solder on it to finish the job. Hold LED in place while you heat each contact, reattach lens, and you are good. I only saw one in a dozen that have a bad power supply...those will have to wait for a day when I have more time. thanks for reading.