Share are two common methods to complete Halogen to LED DRL conversion, one with NCS expert and the other by hardwire. Follow at your own risk!
Method 1 – Use NCS expert to get the halogen light angel eyes as DRL
Here, all complete with BMW ICOM A2 emulator as well as NCS expert. BMW INPA K+DCAN USB cable is also ok. It is a good choice for E series owners.
To disable the DRL (halogen), if you have access to a NCS setup, you just disable it. If you are in Canada or any other country where the DRL are mandatory, only NCS expert will be able to do the change, not GT1. The reason is because GT1 reads the country code when connecting, and disable options that are not allowed for those country.
To get the halogen light angel eyes as DRL (on all the time) and still working as welcome lights, the following lines need to be looked at in the NFRM.
The blue ones are the lines I had to change but I’ve copied the others just to make sure. Once this is done, just go into the OBC and enable the DRL – Voila!
Note that this is for cars with halogen LCI angel eyes, I’m not sure of the procedure for cars with Xenon lights but I believe it’s roughly similar.
Method 2 – hardwired the angel eyes as DRL
If you want to do it the hardware way, like I did, just rewire your DRL like the schematic I put below.
I already disabled the halogen DRL, and hardwired the angel eyes as DRL, but the light output is so low, I would like to have the fog as well for safety.
When there is 12v coming from the car (flashing to pass), the 12v relay kicks in and send that 12v to the halogen bulb. When running normally, there is 6v going to the relay, but it is not enough voltage to trigger the relay, so no voltage to the bulb. The 10 ohms resistor is there to put a load and avoid the burnt light indicator. You will need to install a resistor on each side L-R, but the relay circuit can be used to feed both DRL.
For the Angel Eyes, it is similar. You need to use the red-white wire in the ECU box (red wire with white stripes). You will see many wires with that color, just use the one with the biggest size. They are all ignition 12v feeding different parts of the car. Disconnect your battery before doing connections in the ECU box to be on the safe side. Without cutting the wire, just skin a portion of the insulation, and feed a new wire in the rubber grommet into the ECU box and solder it to the red-white wire and tape it.
Again the resistor circuit needs to be repeated on both sides but the relay can feed both AEs.
I did that modification on my E46 (2004-2011) and my E53 (2011-now) and it works very well.