2016 non pp
I have the DRL switchback kit installed due to passenger HID going out (thought it was a bulb so figured it would be a good time to install this kit) when installing i found water drops on inside of headlight but didn't find any issues with old bulb or new bulb or kit causing the problem at all (preexisting issue)...once installed and put back together it did not fix the problem of bulb issue, and rest of kit works perfectly just not passenger HID headlight (other lights in passenger housing work fine). So i took it to the dealer and they found a crack in the headlight assembly so warrantied the whole assembly(they said including the ballast mounted on bottom). This did not fix the problem. They said that when they unplugged the wiring, water came dripping/lightly running out and its exposed wiring so they have to chase the wiring back to find where the issue (corrosion or burnt wire?) is, they confirmed that the bulb is fine and not the issue but something with wiring and corrosion down the line maybe...does this make sense? how is it exposed wiring and not covered or did i misunderstand him? anyone know what i/dealer is missing here or how to remedy the problem? would it be the fuses? i didn't mention fuses to him... thanks!
Wiring on OEM harnesses terminates into pins, which are pushed into the connectors until they click. At the point where this occurs, there can be a very small amount of wire that is not insulated (in rubber) but also does not make it into the pins. Along with that, the pins are exposed metal. There is also a slight gap between the outer diameter of the pins and the actual wire inside of them, depending on the style of pin/connector used, and the gauge of wire used. All of this allows for a small gap, that water could theoretically get to.
However, even without direct water on the wires, with water in the housing/socket, there is high likelyhood that something could get shorted upon contact with the water, and as such, it seems the dealer is on the correct track.
When I was getting water into my 2011 headlight it definitely made it's way into the harness as well. The headlight was turning on even with the car off at times, luckily for me it all went away after I replaced the headlight