Hi All, I have only seen a few topics on this forum about interfacing arduino with the BMW iBus. I am restoring a 1993 BMW 850CI and I am looking to replace the MID, Radio and temperature controller with a Android based tablet that will communicate via Bluetooth to the Arduino controller. I am not sure what all this entails but am willing to work on this project and looking for advice from others who may have already done something similar. Any references as to where to start would be appreciated. Not sure which Arduino components etc I need to start with to get this project off the ground. Your advice is much appreciated.

How does the communication between application and car works? The app is connected to your car with an USB to I-Bus interface. The is interface is wired with 3 cables to the harness of the head unit and is plugged in the USB port of the Android device. For details on NavCoder software, click here. To use NavCoder on BMW, you'll need a USB iBus interface card. See here: I purchased the NavCoder software primarily to turn off the light control module fault reporting, but this software has a lot more capability. FYI, BMW dealership charges 1.

Hi Robin2, I looked at this thread before posting which was helpful. You were a major contributor to this post so I appreciate your experience in the Arduino space. The additional help that I need is what Arduino hardware controller / bluetooth shield I need so I can get started with capturing the data stream from the iBus via bluetooth. In my research process I did find some additional info on other sites in reference to an android app that was created for a different model BMW so I am in the process of downloading that reference and see how they may of utilized the data captured to then output to the android device.

Also I am gathering info from web on the IHKA controller which controls the different flap stepper motors in the AC/Heat system. From my reasearch I see that there are three Buses that work together the KBus, iBus and MBus. Hi Kish, I've got quite a lot of experience with the iBus and BMW electronics in general, and will try and help where possible.

Hardware wise, you have a couple of choices. Most of the LIN bus transceiver chips (eg MCP2025) can be made to work, but I never found it very easy to deal with bus contention, where two devices are trying to talk on the iBus at the same time. For testing purposes, they should be fine, and are cheap and readily available. Going forwards, I would advise you to track down the Melexix TH3122. This deals with bus contention much better, and has proven totally reliable in my circuit. The nice thing about these chips, is that they both have a built in 5v regulator that can power the Arduino.

Not sure about the Bluetooth side, but I suspect anything that can transmit serial data would work. I would also suggest you get a Resler iBus interface & Navcoder software. Both of these will make bench testing much easier. Hi Robin2 - I think Ian helped out with your question about how to send the ibus info to arduino. Hi Ian, I have seen your posts on this forum and I also have seen some posts on a few bmw forums. Your help is appreciated. So what I understood from your post is that I should use Resler's iBus interface and Navcoder to get all the hex values for the different key presses and various data from the different systems and use this info to help develop the app for Android.