OK Muddy, I got one for ya too!
I'm having a left tail light issue in my '99 Ram 1500 Sport- one bulb turns on in reverse, but not the other (the one with the shorter wires).
The purple wire coming from the front of the truck that hooks into the trailer connector had carbon or something built up inside when I stripped it (even though when scraped off, the wires looked fine), but the wire was fine on the other side of the connector (which goes to the bulb). The purple wire was NOT the one connected to the bad terminal.
Thinking it was just a bad connection, I cut the 2 sides of the connection out and then spliced in a new connection, so everything is connected properly. My tail light now turns on, but in reverse only 1 of the bulbs lights when both should be. If the wire looks charred like that will it still conduct properly if scraped clean on the contacts, or is the wire useless? I forgot if the purple wire is one that goes into the bulb that won't light, but I'll check when I get home.
Any input in the mean time would be greatly appreciated!