Apr 29, 2018 - I've always wanted to mod my phone button to be the DSC button, especially on my X5, as in the winter I'm always turning my DSC on and off.

*** Project: Arduino & BMW K/I-Bus Interface *** This project was born because I chose to do a simple task the hard way. I have a hard-wired radar detector in my E46 BMW – an Escort Redline. The wiring kit includes an alert LED which flashes whenever the radar detector picks up a police radar band.

The LED was the perfect brightness during day time, but was a ridiculously bright eye sore in the night time. Instead of simply using a photo-resistor to solve this issue, I decided I wanted to use the already available light sensor in the car. The Rain/Light Sensor is mounted on on the top center of the windshield. It’s purpose is to: 1) Detect rain on the windshield to automatically turn on the wipers and set a proper wiper speed 2) Detect ambient lighting to control automatic headlight operation It turns out the Rain/Light Sensor is connected to the cars’ internal serial communications bus. This is when I discovered the world of the BMW I/K-Bus. The K-Bus is a standard bus protocol for automobile electronics. In other words, it is a way for devices within a car to communicate with each other.

On the BMW, there are several devices on this bus. These include: • Radio • MFW Steering wheel buttons • CD Changer • Light Control Module • etc There are many possibilities when you are able to read and transmit on this bus. The description of this circuit can be found. Putting things together: Assuming you already own an Arduino (I used an ), the Bill of Materials (BOM) is: • Diode 1N4148 • Resistor 10 ohms • Capacitors: 1uF 47uF 100pF • Melexis TH3122 IC • SOIC to 16DIP adaptor • Small breadboard • Breadboard wires • (optional but recommended) Tools/Equipment: • Soldering iron (for the TH3122 IC) Links & details for Bill of Materials items are shown in the excel sheet below (Available in the section, “Physical Layer” folder). I soldered the TH3122 onto my SOIC to 16DIP adaptor, then assembled the Arduino breadboard according to my schematic.

The is very useful for using software serial. The time discography torrent. I am using pins 7 and 8 on the arduino. FYI, the signals must be crossed – Tx on arduino to Rx on the converter. Pin 7 on the arduino will be Rx and 8 is Tx. You can use any serial monitor software for debugging – I personally prefer.

Photos for reference.