I have had to replace the bulb holder on my 51 plate nissan micra as part of it has melted. I've got a replacement unit, stripped the wires of both the car fitting and the reppacement holder, however the car has black, red and green, and red and blue cables, while the replacement unit has red, blue, and yellow cables. How do I tell which is the correct one to use?
There is a wiring diagram here. It suggests that, for the right hand headlamp, Black is ground, Red/Blue is low beam, and red/green is high beam.
It can't, however, tell you what to use in an aftermarket replacement - did that come with any instructions? Otherwise compare it to the original unit and try to work out which is which!