Hi, Newbie here, I have a 2014 RR Sport Autobiography. The Rt head-lite went out and I had the bulb D3S & Ballast replaced several times. Sometimes the lite worked temporarily and sometimes not at all.
Any help is appreciated.

Sounds like a wiring defect probably to the ballast. when its failed check the 12v AND THE EARTH to the unit.
You could run a wire from the failed one to the good one to by pass a failure in the wiring, Always listen to old people or when they die you will live on in ignorance.
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