Resurrecting a Dead DMX Light Bar

This time around I'm fixing a DMX-controlled light bar. It's brand new but arrived not working…completely dead. In my experience, “completely dead” is better than “partially working” which is probably better than “working some of the time”. “Partially working” means you need to know a lot about how it is supposed to work. And “working some of the time” means it will probably work when you don’t want it to, which makes it very difficult to find the fault.
In this video I'll get the basic functions working. In a later video I'll check out the DMX functions.
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