A friend of mine brought me a non-working LED light some time ago. It was an huge heavy-duty light from some agricultural machine. It did not light up anymore and I agreed to see if I can fix it. The light had aluminum case with cooling fins around it.
The front glass covered a green PCB with LEDs soldered onto it. The PCB was made of some kind of aluminum compound, possibly for better cooling. It had 16 leds, divided into groups. Most LEDs were burnt out, measuring either short or open circuit. Some lighted up dimly when measuring with a digital multimeter.
At the first I contacted the support of the light manufacturer, TYRI, to obtain a new PCB or get the make/model of the LEDs in case I need to resolder them myself. However, they kindly offered a replacement light despite the warranty being expired. I also had to send them current light back.
At first, the light was sent out using a non-tracked service, possibly the standard mail service. Unfortunately, it never arrived. Numerous attempts to contact post services led to nowhere, there was no trace of the package. Then, some time later, after discussing with TYRI support, they decided to resend it, with a tracked service. 3-4 days later the package arrived! Their customer support completely rocks!.