Richard Solomon
10-09-2000, 08:42 AM
Here's some information I've gathered in my quest to integrate a Nokia 2160 car kit into my MY'00 A6. First, reference Ed Palisoc's FAQ for the A/S4: (See below) which I found to be invaluable. Secondly, note that the in-car microphone for the A6 (at least mine) is in the front dome light assembly. There are two blacked-out vented areas, the driver's side one has the Audi microphone behind it. In addition, the car Owner's Manual tells you how to remove this assembly because you need to do so to utilize the emergency sun roof crank! Finally, I can confirm that (at least for Bose-equipped cars) there <b>is</b> a separate speaker for the phone - a small (~2") speaker in the driver's side B pillar a little below shoulder height. Ok, one more thing: the DB25F plug is located just above and to the rear of the CD-changer bracket in the trunk (you'll have to pull the toolkit to see it).
I took a bit of a different tact with my install than Ed took with his. Since the Nokia 2160 car kit uses an 8-conductor RJ45 cable between the cradle and the main box, I chose to just use the in-car handset wiring as an integrated cable and put the cradle in the armrest and the main box in the trunk. (This does away with the Nokia handset option, but I didn't find that problematic.) Also, since I've not been terribly unhappy with the reception of the phone when using it freehand in the car, I just took the short Nokia cradle-antenna cable and hooked it to a little rubber ducky antenna which sits in the armrest. Nothing super fancy, but it works, and I didn't have to route coax cable (or any other cables) around my car! (Neither did I end up with an ugly cell-phone antenna visible outside.)
My cabling philosophy was such:
-Plug Nokia cradle cable as-is into RJ45 jack in armrest
-Plug Nokia cradle antenna into rubber ducky, mount ducky in armrest somehow
-Build DB-25M cable to all Nokia kit plugs
-Put Nokia car kit box in trunk underneath CD changer
-Build DB-25M to DB25F adapter containing mic pre-amp power/volume control circuit
-Plug my cable into the adapter and the adapter into the car cable.
This gave me a trunk cable which plugs right into the car wiring and has all the Nokia plugs coming out of it. By doing this, in combination with building the mic pre-amp circuit separately, I can easily recable for another phone w/o having to rebuild the circuit. This way, I avoided all the disassembly of various car parts (center console, rear seats, etc) which Ed had to go through.
I also dislike cutting original cables so I got connectors as follows from Radio Shack:
Speaker: 1/8" Mono jack
Microphone: 3/32" Mono jack
NOTE: Both should be wired as tip-positive.
NOTE2: The 3/32 jacks I got from Radio Shaft were <b>really</b> poor quality. Of the pair in the package, one was DOA - no connection at all to the tip! The second had some kind of intermittent connection which I chased for 2 days straight before giving up and cutting the original mic cable :(
I used a DB-25 male connector with the crimp pins as I have the tool ($3) to insert and extract them, and it made fixing my wiring goofs MUCH easier than resoldering to solder cups. I cut a Cat-5 ethernet patch cord in half and plugged one half into the armrest (just for testing connectivity) and used the other half to be my cradle connector to the kit box. As others have noted, Ed used an odd numbering scheme for the RJ-45, so I had to reverse the pin order from his diagram. (I actually crimped pins on all 8 conductors but only plugged in the two end connections to the DB-25. Then I put a 9V battery between the corresponding two wires on the cable I had plugged into the armrest. Reading the polarity of the 9V now in the trunk told me I had to reverse the pins. After that, the other 6 connections were easy.) I then took power for the car kit and tied it to some smaller wires running to pins which I inserted into the DB-25. I made cables between DB25 pins and the 1/8" and 3/32" jacks for speaker and mic respectively.
I never got any sort of mic signal at all from the in-car mic, but I figured "Heck, w/o preamp power it won't ever work...don't worry." I then set out to build the mic preamp power / volume control circuit which Ed shows in his FAQ. Rummaging through my spare parts bin, I found the coolest little RS-232 patch box. About the size of a gender bender, this gizmo had sockets for every pin on each side (male/female) and some sockets in the middle for junctions. I actually plugged a 50K pot into the patch box so that it hooked one leg up to a ground pin, and the other two legs to the junction areas. Then it was just a matter of plugging in resistors and capacitors to fill out Ed's circuit. (I did have to run power and ground across the back because I didn't have enough junction sockets to make everything route perfectly.)
I set the pot at 1/2 scale (25K ohms) and plugged in the adapter between my new cable and the car...no joy. To make a very long story short, after proving I had connectivity all the way back to my 3/32" jack, I cut it off and wired to the original Nokia 3/32" Mic jack and everything worked fine! I racked up a bunch of cellular minutes playing with the pot setting to get a volume that I liked. I also wasted time appreciating how an incoming call mutes the radio, then unmutes when the call ends. :)
Hope you find this useful,
I took a bit of a different tact with my install than Ed took with his. Since the Nokia 2160 car kit uses an 8-conductor RJ45 cable between the cradle and the main box, I chose to just use the in-car handset wiring as an integrated cable and put the cradle in the armrest and the main box in the trunk. (This does away with the Nokia handset option, but I didn't find that problematic.) Also, since I've not been terribly unhappy with the reception of the phone when using it freehand in the car, I just took the short Nokia cradle-antenna cable and hooked it to a little rubber ducky antenna which sits in the armrest. Nothing super fancy, but it works, and I didn't have to route coax cable (or any other cables) around my car! (Neither did I end up with an ugly cell-phone antenna visible outside.)
My cabling philosophy was such:
-Plug Nokia cradle cable as-is into RJ45 jack in armrest
-Plug Nokia cradle antenna into rubber ducky, mount ducky in armrest somehow
-Build DB-25M cable to all Nokia kit plugs
-Put Nokia car kit box in trunk underneath CD changer
-Build DB-25M to DB25F adapter containing mic pre-amp power/volume control circuit
-Plug my cable into the adapter and the adapter into the car cable.
This gave me a trunk cable which plugs right into the car wiring and has all the Nokia plugs coming out of it. By doing this, in combination with building the mic pre-amp circuit separately, I can easily recable for another phone w/o having to rebuild the circuit. This way, I avoided all the disassembly of various car parts (center console, rear seats, etc) which Ed had to go through.
I also dislike cutting original cables so I got connectors as follows from Radio Shack:
Speaker: 1/8" Mono jack
Microphone: 3/32" Mono jack
NOTE: Both should be wired as tip-positive.
NOTE2: The 3/32 jacks I got from Radio Shaft were <b>really</b> poor quality. Of the pair in the package, one was DOA - no connection at all to the tip! The second had some kind of intermittent connection which I chased for 2 days straight before giving up and cutting the original mic cable :(
I used a DB-25 male connector with the crimp pins as I have the tool ($3) to insert and extract them, and it made fixing my wiring goofs MUCH easier than resoldering to solder cups. I cut a Cat-5 ethernet patch cord in half and plugged one half into the armrest (just for testing connectivity) and used the other half to be my cradle connector to the kit box. As others have noted, Ed used an odd numbering scheme for the RJ-45, so I had to reverse the pin order from his diagram. (I actually crimped pins on all 8 conductors but only plugged in the two end connections to the DB-25. Then I put a 9V battery between the corresponding two wires on the cable I had plugged into the armrest. Reading the polarity of the 9V now in the trunk told me I had to reverse the pins. After that, the other 6 connections were easy.) I then took power for the car kit and tied it to some smaller wires running to pins which I inserted into the DB-25. I made cables between DB25 pins and the 1/8" and 3/32" jacks for speaker and mic respectively.
I never got any sort of mic signal at all from the in-car mic, but I figured "Heck, w/o preamp power it won't ever work...don't worry." I then set out to build the mic preamp power / volume control circuit which Ed shows in his FAQ. Rummaging through my spare parts bin, I found the coolest little RS-232 patch box. About the size of a gender bender, this gizmo had sockets for every pin on each side (male/female) and some sockets in the middle for junctions. I actually plugged a 50K pot into the patch box so that it hooked one leg up to a ground pin, and the other two legs to the junction areas. Then it was just a matter of plugging in resistors and capacitors to fill out Ed's circuit. (I did have to run power and ground across the back because I didn't have enough junction sockets to make everything route perfectly.)
I set the pot at 1/2 scale (25K ohms) and plugged in the adapter between my new cable and the car...no joy. To make a very long story short, after proving I had connectivity all the way back to my 3/32" jack, I cut it off and wired to the original Nokia 3/32" Mic jack and everything worked fine! I racked up a bunch of cellular minutes playing with the pot setting to get a volume that I liked. I also wasted time appreciating how an incoming call mutes the radio, then unmutes when the call ends. :)
Hope you find this useful,