So I am completely perplexed here. I ordered some LEDs and projector headlights to replace the factory headlamps as I wanted the bright white lights. At the harness for the bulb I read 12V low and high beam, no visible change at all. However the LEDs run about a million times brighter on high beams and are putting out about 1 candle power on the low beams. Does anyone know what the issue is here?

 

Cars with a cannbus (MINI's included) typically run halogen bulbs at a slightly reduced voltage....it does that by pulsing the power to them....this is done to save power, and lengthen the life of the bulbs...
When folks switch to xenons, they typically add a capacitor to the circuit(usually included in the kits) or have to get the car coded to fix the issue....
Guessing something similar is going on here.

 

I tried both with and without capacitance. It must be a pulsing that I can not see on a multimeter. I can't think it limits current as LEDs are capable of running on very little power. I read 12.4v DC rock solid on low and high beam. I switched over to AC to see if that different between low and high, it was the same as well. I checked voltage from both conductors to ground as well and they were the same.

With capacitance added I get a full brightness strobing about every 3 seconds, without capacitance I get a very dim flickering. I was going to try to wire them up via relay and a 12 volt source to eliminate the issue but the low beam bulb signal isn't enough to change the state of a relay either.

Tomorrow I will call the dealer and see if they have any fixes or advice for me.

 

Coding the car for factory xenons would probably fix this. I had similar issues when retrofitting OEM xenons.

Do they flicker with the ignition on but the engine not running?