und hier die neueste Anleitung von Johan
Killing the LKM 'low beam' message with aftermarket Xenon
Text kopiert, Bild ist im Link:
Killing the LKM 'low beam' message with aftermarket Xenon
I promised someone I'd look into how the LKM works to kill the "Low beam" message when after market Xenon is installed. After a long time I finally have some days off so I had a look at the LKM.
For the low beam lights the LKM uses a shuntresistor embedded in the PCB. This resistor is used to measure the current going to the lamp. When the light are functioning OK this gives a voltage drop of a couple of mV over the resistor. This voltage is sent to a AD22001 IC this is an IC made to check bulbs in cars. It seems to compare the voltage drop to a preset value. The result of this comparison is sent to a HCF4021 IC which converts parallel inputs to a serial datastream which goes to the cluster.
If you pull down pin nr. 1 of the HCF4021 as I did whith a resistor you will kill the low beam message alltogether. I used a 20 Ohm as it was the first I could grab. But I'd try a 1k so see if it also works and use that.
I did use an LKM-B (basic) instead on an LKM-L (luxuray) which is in all the 7s. But the principle should be the same. The LKM-L has two HCF4021 ICs and you will need pin 1 of the right most IC.
As always this worked on my LKM no telling if it will work on yours. And if it will stay in one piece. Your car, your responsibility.
A picture of the modification I did on my desk: