Since I had received the first two of several 20W drivers and LEDs ordered from different ebay sellers I decided to go ahead and upgrade my fake 20W bench floodlights to their full 20W rating.
I decided to video it because it shows what's involved in changing the drivers and LEDs in standard LED floodlights. This means that anyone with a faulty light can get it going again, since there are really only two components.
You could also mod your light by changing the colour from cold white to warm white or vice versa. Or perhaps use one of the high power coloured LEDs instead for effect lighting.
If your light was having thermal dissipation issues you could also lower the drivers power rating from maybe 100W to 50W.
Most of the lights in the 20, 30, 50, 70, 100W range use a standard LED platform with a matrix of 100 LED mounting positions on it that are populated as required. The LEDs tend to be wired in series circuits of ten 1W chips and then groups of ten are paralleled to make up the desired wattage. It follows that if you have a 20W driver you can actually use a higher power LED array since the voltage will be the same and the current will just get distributed through more LEDs. In this case I chose to use a 20W driver to run a 50W LED to give the LEDs an easy life at less than half their normal current.
The video is self explanatory, but it's worth mentioning that I had already extended the cable length on the floodlight. If you can actually use the tiny length of cable that comes pre-fitted then you only need to thread it through the cable gland. You don't need to use soldered joints and heatshrink sleeving. You could use crimps or even terminal strip to make the connections. Just make sure the earth/ground connection is attached to the metal case for safety.
The positive side of the LED seems to be identifiable in all the LEDs I've used, by the location of two extra holes right through the body and heatsink plate of the LED. Possibly also used for alignment in manufacturing processes.
If your light has a passive infrared detector on it for detecting the presence of people then it has three wires that are connected as follows. The neutral (blue in Europe) that is commoned with the incoming neutral and the driver. The live (brown in Europe) which goes directly to the incoming live. And finally there will be a third switch wire which will probably be a different colour like red. This is the one that goes to the LED drivers live connection so it can switch the light on and off. If you have a faulty PIR you can either bypass it for continuous operation by just connecting the LED driver directly to the incoming mains supply, or you can probably get a new one cheaply by buying a basic PIR LED floodlight purely to rob for the PIR sensor unit. The power rating is not really an issue, since even the most basic PIR should handle up to 100W or more.