Hid stuck on high beam
My harness has a power lead and two grounds then it has one plug that plugs into the factory harness and two plugs for the hids( one for each light) so not sure what you mean by it has its own high beam plug.
if its stuck on hi beam, that means there is either an electrical fault or it's physically stuck. the his is a solonoid that thet trips the cutoff shilt, it's default state it shield up (low beam), once power is applied, it flips down to allow full light , if power is lost, or switched, it well default back to low. so if it's stuck in high, it;s an issue with the harness, or the shield is sticking. my guess would be a harness issue since you said it was flicking on and off then stayed on high.
I have a brand new morimoto harness in my hands right now, there is a seperet plug that goes to the high beam silonoid on each side along with a plug to each ballast. for now, just unplug the high beam silonoid plugs untill you get a new harness.
I have a brand new morimoto harness in my hands right now, there is a seperet plug that goes to the high beam silonoid on each side along with a plug to each ballast. for now, just unplug the high beam silonoid plugs untill you get a new harness.

