09-26-2012, 11:28 AM
Join Date: Feb 2012
Mein Auto: 2012 F02 750Lix
For all of you wondering why it is so difficult to get these electrical mods working on the F01/02... I think I have found the cause... and possibly a solution (more on the last part to follow).
I was having a BMW tech who also has his own shop install some HID driving lights on my '12 F02 M sport in addition to the HID angle eyes from Alpine I installed a few months back. Needless to say we ran into our share of problems but learned a lot in the process.
Long story short, it turns out that the new BMW's use a pulse modulated current throughout the car to power everything. This apparently saves a lot of copper wire and weight. In fact the new cars have half the wiring than the previous model had. The current in this new set up is constantly switching on/off to all electrical components which are designed for this. As you can guess, this relies heavily on programing and solid state technology to work.
The relays that are part of the kit (and many other kits) are failing with such frequency because they are mechanical and essentially buzzing on/off due to the pulsed current which they aren't designed for. I am now running a nonmechanical solid state relay which addresses this first issue but unfortunately there are additional problems.
The current in this electrical set up also fluctuates between 12V with just the battery on and 14+ volts while the alternator is running which is likely tripping the ballasts resulting in the sometime on sometimes not nature of these lights. This requires a capacitor to be added into the lighting circuit to maintain a steady 12V current.
Then we have the resistor problem, to trick the faults codes into thinking a bulb is still in place. On inspecting the one that was part of the angle eye kit (Black cylinder attached to harness), it looked like it was about to explode and had severely swollen after only little use. So this too has to be beefed up and replaced.
My mechanic is almost finished with the project that started as a weekend install. Between all the trial and error as well as waiting for new parts its now been 3 weeks. I can't wait for the bill on this! lol
I will post a wiring diagram, and component parts that need to be replaced once I'm sure this setup is working. I can already tell you though, that it won't be cheap as the solid state relay alone runs $180.
Else where on this forum are posts for supposedly error free LED's for the F01/02.... something to think about although they are likely not as bright! Some have also reported yellowing of the angle eye fibers from HID's so that may still be something else to contend with.
In the mean time... happy motoring!
2012 BMW F02 750LiX, Alpine White, M-Sport, Dinan Stage 5, Dinan Exhaust, H&R Sport Springs, Coded, Paddles.
2012 BMW F12 650iC, Mineral White, Dinan Stage 3, Dinan Exhaust, Dinan Shockware, Coded.