Thread: 2003 BMW M3 Custom Dash / Overhead Console

I run copilot 2003 due to the screen size issues, but the maps are farily dated.

I use the I-Bus for volume control and app switching. The only software I have for it is some stuff I custom wrote into my in-progress application. You will not be able to do much with the I-Bus since you kept the radio. If you don't have the BMW phone (seriously, who does) you can trap events from the two phone buttons on the steering wheel. You may also be able to send commands from the pc to the radio to tell it to switch modes, etc. There might be a way to output some text to the radio screen also. Look to the HackTheIbus group on yahoo groups for more.

As a side note, I get more emails and PM's from people about the I-Bus than anything else. I think I have said this before, but please do not contact me (sometimes repeatedly) about I-Bus stuff. I do not have any software that works under windows to do anything with the I-Bus. I abandoned my efforts under windows a long time ago. I also, do not know very much about the I-Bus aside from using it to 'listen' for events. In all likelyhood, using the I-Bus will mean that you are going to be writing your own software to communicate with it. /End PSA

where is the 3-pin i-bus interface located on the m3?

It's in the trunk on the left wrapped up in a bundle. You can access the I-Bus on the three wire connector for the telephone or in the CD changer harness. The best way to find it is to turn the car on (start the engine, turn the radio on) and use an oscilloscope between GND and your probe to find the IBus wire. The I-Bus is normally 12V (so it looks like a battery wire), and goes to 0V when transmitting a bit, so you can see these on a scope. In the 3-wire harness you have 12V Batt, GND, and Ibus. Don't get them mixed up or you will blow the telephone fuse!

thanks, gork!

saves the trouble of running a serial cable across the car.

I don't do anything to keep it cool. It's a via C3 (EPIA M1000 ezra core motherboard) so it hardly gets hot. I have had no temp problems from 9degF to 100degF outside temps. You are going to have a hell of a time with keeping that Celeron cool if you live somewhere hot.

You should look for an external firewire or USB2 (must be usb 2.0 480mpbs!) drive enclosure that will hold a 5.25" optical drive and take the bridge board from that. Anything that will do this will support ATAPI devices and thus a dvd rom. You will have trouble finding a suitable adaptor that is sold standalone.

You are correct about all the other stuff you need.. slimline->ide adaptor and a bridge board. You will have to run a firewire cable and 5 and 12v from your computer's psu up there to power the drive, and probably the bridge board will take 5v also.