Hello,

I’m currently in the process of retrofitting a bi-LED projector into the factory housing of my '06 xB, but I’m having some trouble with the wiring and was hoping someone could provide input on how to tackle it. The projector has two sets of wires—positive and negative for the low beam, and positive and negative for the high beam solenoid, which activates a flap to change the beam pattern.

I can’t figure out how to connect the projector to the factory H4 connector. I have the necessary wires and connectors, but when I probe the connector, it shows 12V on the side prongs and ground in the middle when the low beam is on. When the high beam is switched on, something changes that I can’t quite figure out.

Does anyone know how to build a harness for this setup? I saw a YouTube video mentioning the use of resistors, but after trying that, I got a working low beam while the high beam just caused the light to dim.

Any help would be appreciated, thanks!

 

With an alternator, you shouldn't need resistors (except for turn signals), as the controller in the alternator can reduce the charging load, It's different with motorbikes as they normally have a generator with fixed output and the regulator has to dump the excess current as heat.

Are both elements in the standard bulb on with the high beam activated?
Should be able to tie both grounds together.

I'm not an electrical guy though...

 

Does this help?

 

Thank you so much for sharing the information.