I had this problem in my Falcon, turns out it was a combination of things. The fuse was bad, which was the first and biggest issue, then as me and my friend found by taking the dash out and testing all the light bulbs with a volt meter for continuity, there is a large dead spot in the switch. If i turn it at all off the mark then the lights don't show at all, but if i keep it right on they work great

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