Kmoy's DIY $5 Aux Cable (Lots of Pics)

[markb121]

Great Post & guidance for a DYI version of the cable set offered by BMW (see Bav Auto).
I did however run into a couple of issues.
-The removal of the cup holder is not related to the rib(s) shown in a prior post. There is a cover piece that is part of the cup holder assy in my 2003 540i. The edge of that cover part likely hung on the console bezel. So one need to make sure that the putty knife goes over that cover and not under it. I manages to pull out the cup holder but broke two snap tabs that held the cover on. Nothing some super glue could not fix but a nuisance none the less.

-Now to operation. At first I could not get the system to recognize the iPod. The player was down on battery charge so I had it connected through an iPod accessory (DLO Transdock Micro FM transmitter) This device, besides acting as a power supply for the iPod and transmitting on low power FM also has a "Line out" 3.5mm jack that I have used in other vehicles & mobile audio players that have an aux in with fine results. I had plugged the Line Out form the Transdock Micro into the Aux input as described in this post & No sound... I then rechecked my home made cable for continuity and the connection at the back of the Business CD player. All was correct. So later I took my Motorola android phone & launched Pandora. Now I got sound & the BMW unit recognized the Aux device's input. So then I charged up the iPod & plugged it in directly via the HS jack. It worked too.
Here's the weird part. The business CD player will not recognize the iPod's HS jack output if anything is plugged into the bottom connector. The Transdock only as a power supply to the iPod with audio direct tot he HS jack, the Transdock using the Line Out from the dock into BMW, not even a cheap Cigarette lighter USB supply powering the iPod. The exact same thing happens with the Motorola XT907 phone. It work fine under battery power but as soon as a 12V power supply is plugged into the uUSP receptacle the BMW head unit toggles to the next available source. CD if one is installed or radio if no CD is present. But when I used an AC plug-in supply, not one powered by the car's 12 system, both the phone & iPod worked fine and the devices showed to be charging. Perhaps there is a common ground issue with the Pin 10 audio ground & the vehicles Cigarette lighter adapter's ground which causes the CD player to lose the detection of the aux device.
The car is without Nav or CD changer. Just the single Business CD in the dash.
Anyone experience this & have a remedy?

[01din]

To resurrect.....

'99 540iT (mfg date 11/98), original radio head unit and tape cassette. I also have separate CD unit, e39 OEM Alpine (mfg date 4/2003). Photos of units and plugs attached.

I'd like to install an aux cable via the new CD player, so I need to replace the cassette with it. CAN I EVEN INSTALL AN 03 CD PLAYER INTO A 99 HEAD UNIT?

I'm okay with wiring and soldering if needed.

Thanks everyone. ZOFj%e+QTWaMvPnBET5QFA.jpg+DaZvIgRTAKfs6TdD%XoPg.jpgTAUsDovYTKCBAZ4tWr6rGA.jpgiMqP98lNTGqobBkI1H1Onw.jpgJ0STFuC6QaiU1WxIDG+i5Q.jpg