Here is an except from my Mega I.C.E DIY that I did over the weekend.
The USA-Spec is a beautiful little creature that performs perfectly in every way! PART SEVEN: Adding an iPod Data Integration unit.
Now this part will complete your DIY project and pretty much put a nice cherry on the cake since iPod integration is a MUST HAVE for those of us with iPods and iPhones.
For folks that do not have a BMW Sirius Receiver, and do not have a BMW Factory CD Changer in the trunk you can breeze thru this part and connect your DICE or USA-SPEC or other Data Unit to the pre-wired CD Changer cables that are in your in the trunk as shown in PART SIX ( the felt wrapped cables that I'm seen unwrapping to connect to my Sirius Receiver).
If your BMW E46 did not come with any prewiring for the CD Changer you will need to buy the Data Link Cable BMW Part# 61128374683 which costs around $40 to $60 at the dealership and install it yourself from the Data Link Port #1 to your iPod Data Unit. Those doing it this way will have the advantage of leaving everything inside the cabin of the car since you can opt to keep everything behind the dash area.
Those who are using a Sirius Receiver or a CD Changer already in the trunk will have to get the Slave Data Connector OEM Part #84110150526 and use it to connect the iPod Data Unit directly to the Sirius/CD Changer which will in turn connect the iPod Data Unit to the car. So when MODE is selected after SIRIUS you will access your iPod as if it is a CD Changer.
Picture of Slave Cable below borrowed from SNA77.
I previously planned on using Data Port #2 on back of the business CD53 Radio to support the iPod Data in the identical way that Data Port #1 supports the CD Changer/Sirius but I was wrong.
Port #2 will NOT WORK
on its own for Data Input support. You can add your iPod Data or 2nd Data Source (IE. CD Changer slaved to Sirius) with a Slave Data Extension Cable branching off the Sirius Receiver/CD Changer. In this case the BMW system gives hierarchy to Sirius as master always and the Data iPod or CD Changer Slaved off of it. If Sirius isn't present but a CD Changer is then the CD Changer must be the Master to Data iPod.
That said you most likely CANNOT have ALL THREE (iPod/Sirius/CD Changer) in your car at once using just the normal Data Link Pre Wiring Cable and Slave Data Cable. INTERESTING SIDE NOTE: There is a DIY-mentioning from last year where a member at e46fanatics BMWAudio32 from Columbia, SC discovered, while trying to remedy the DICE/Sirius ghost feedback/alternator background noise, that you can actually splice the trunk bound ends of the main Data Link Pre-wire Cable and create two sets or multiple sets of Data Link ends off the main cable leaving the Data Link Port #1 on the back of the CD53 head unit. Then with placement of a homemade toggle switch along the junction where the separate branches meet BMWAudio32 was able to choose from multiple Data Sources (whether it be iPod, Sirius or CD Changer) in his car by flipping the homemade switch between the branches when the SIRIUS/CD CHANGER MODE was selected. This method successfully "fooled" the head unit into thinking there was one only data source when they were actually multiple. The only downside is the DIY time and skill required as well as the non-OEM look of the homemade switch placed in the cabin. Other than that it allowed for multiple Data sources that did not interfere with each other at all and eventually created the best solution for dealing with DICE/Sirius/CD Changer interference noise and issues when slaving various Data Sources.
Read More About that here: DICE - Sirius slave cable - OEM part available? - E46Fanatics
That brings me to my choice in the USA-Spec which was very well reviewed and introduced to the e46 community by Steve325i from e46fanatics. As a less popular unit than the DICE, The USA-Spec is cheaper and has all the features of the DICE including an RCA Aux In Port. The only reported disadvantage of the Spec to the DICE is you are only allowed access to up to 5 User-Set Playlists (Or the option to just Play ALL SONGS on iPod) while the iPod is in fully integrated mode.
The DICE allows for access to more or all the Playlists on your iPod and text display is given for the Playlist. The USA-Spec was fine for me since with Sirius, AM/FM, 100s of songs on my MP3 Data CDs, and AUX input in my car I already have unlimited access to hours upon hours of fresh music. Accessing only 5 Playlists off my iPod would not kill me or be a deal breaker. Albeit the 5 User-set Playlist can have unlimited amount of music in each playlist with respect to the size of your iPod. So you CANNOT argue that the Spec gives you access to "less" music than the DICE would. It just gives you access to less playlists than the DICE would.
Said and done my install, after a few Darwinian/Homer Simpson moments, ended beautifully. The USA-Spec, when done properly, installs and works smoothly without any of the reported issues you get from the DICE. VERY IMPORTANT NOTE:
You MUST fully unplug your CD53 Radio and unplug your car's battery before connecting the iPod Data Module to the car. I forgot to do this on my first attempt and my Odometer/OBC and Radio Display fizzled and pop and the text display went all Klingon on me.
I quickly disconnected everything immediately and was lucky enough to not damage anything.
After the second install attempt went smoothly I opted to run the Spec's long Data Cable into the cabin from the trunk to the USA-Spec Module in the glove box area. The Spec also comes with a lengthy iPod Cable, though not as durable as the burly Data Cable, which I snaked under the centre console/arm rest area.
Unlike others that did this before me I did not drill holes or cut and splice cables to squeeze my iPod into the E46 Armrest's tight lid pocket. Nor did I want my iPod out in the open and in the way.
I wanted to get in the car plug the iPod in and lock it away in such a place that it would be fairly immune to theft (IE. Not in the glove box or ashtray),
not taking up visual space in the dash/console area yet still be easy and quick to access.
The best place I found was under
my Euro Tray. There the iPod Touch could fit, be out of the way and accessible in seconds by pulling up the Euro Tray (or cup holders if that is what you have). NOTE:
the coin holder that rotates/flips up (it usually comes standard behind the cup holder on the USA E46 cars)
will not give enough space for a large size iPod (like a Touch). You will need to replace it with some version a Euro Tray or the flat storage tray that sits behind the cup holders/or short Euro Tray and replaces the coin holder. In the picture below the Red X denotes what NOT to get. The other segments are fine for storing your iPod under. (Also there is a very rare segment that is a small flat open holder tray) not shown here that directly replaces the coin holder in the rear space behind the either the USA cup holder or short euro tray that will also work. NOW ONTO THE PICTORIAL DIY FOR PART SEVEN: