SpideyTT!!!

I just finished the 3rd incarnation of a Motorola V60i install in my 2001 Q 225 TTR.

The story in short: Phone installation pro botched the job. I have fixed it myself improving it significantly, but there is still work to be done, and I have some questions for those who have done more electronic work on their TT, or with Motorola phones. When I have it working perfectly, I will post V60i install instructions to this forum.

The details:

As you all know, the phone which Audi offered with the 2000 and 2001 models was an analog monstrosity. Dealer suggested that I continue using my existing phone (a Verizon Motorola V60i) and have a handsfree installation done in the car.

TRY 1: Brought car, phone, motorola pro-install handsfree kit and the audi phone mounting bracket (u-shaped one) to an "expert pro" phone installer. He managed to adapt the bracket to hold the cradle from the HF kit. HF kit equipment was "mounted in an excellent location under the dash". A patch antenna was mounted high on right side of windscreen, and microphone mounted at right pivot of driver's sun shade. Cable from phone to HF kit is "sneaked" into dash between carpet and passenger side front center trim panel.

RESULT 1: Cell phone calls do not mute radio, and are not routed to the radio speakers. Installer says "I am reluctant to do that on these euro cars because the radio sometimes cuts out". Obviously he never bothered to read the instructions in the owners manual about the radio code, or do any research on how to install into this car. On the way home, I discover that I can not open the center storage compartment to get to the gas filler door release. The HF kit has been "stuffed" into the space reserved for the cover of the center compartment when open. Aside from all of this, the phone works OK, at least with the convertible top closed.

TRY 2: Brought it all back to "pro install" guy. This time I watch him "fix" the problem. HF kit speaker is "re-stuffed" into dash to right of glove box. Electronics package is shifted farther forward so as to "eliminate" interference with with the center compartment cover.

RESULT 2: After completion, I note a broken off mounting tab from a trim panel on the floor. Center compartment still doesn't open completely, but is better than before. Phone HF speaker can barely be heard even with volume at maximum. I also notice that the phone reception is poor (worst than before), and that my car has now developed a rattle at 3500 RPM.

TRY 3: After research on the web, decide to have a go at it myself. Ripped out the old install, discovering that the power feed for the HF kit had been routed to the fuse box via the brake pedal mount. It is a miracle that it didn't get cut and short out before I noticed it. Also noticed that cause of poor reception was a loose antenna connection. Remounted HF electronics package to knee bar forward of glove box. Manufactured a simple [no electronics] RJ-45 adapter cable and a DB-25 jumper plug [thank you Jeff Bipes] to bring power and radio connections from the HF electronics package to the TT's wiring harness and on to the radio. Discarded speaker from HF kit. Left antenna and microphone from HF kit in place (and in use) for now.

RESULT 3: Radio is correctly muted when phone is in use, and audio from phone is routed through radio speakers. Phone is controlled correctly based upon position of ignition switch. Rattle at 3500 RPM But problems remain to be resolved. The audio from the phone is too loud (even on the lowest volume setting), the microphone is picking up only noise when the driving with the top open, and there are ugly exposed cables from HF kit to telephone cradle and RJ-45 jack.

FUTURE: My next step is to make use of microphone built into the instrument cluster to see if this will help with the road noise. Next is to eliminate the cable clutter. I would have liked to mount the electronics package at the DB-25 connector behind the passenger seat, but this is impossible because the Motorola HF kit requires 10 conductors between the cradle and the electronics package, but only 8 are available on the RJ-45. Perhaps I can mount the electronics package under the passenger seat - but then I will have problems routing the antenna cable (runs directly from cradle to antenna with this kit) which must either go to the TT's plug back near the DB-25, or to the patch antenna on the windshield.

QUESTIONS:
1) Does anyone know whether the Motorola handsfree kit supplies the 12 volts which the TT microphone needs?
2) Assuming that it does not, does anyone have an accurate schematic for the circuit to correctly feed 12 volts to the microphone?
3) Does anyone have any suggestions about where to mount the HF kit's electronics package?
4) Is there a good way to route an antenna cable from the passenger compartment to the TT's antenna connector next to the DB-25 in the cubby behind the passengers seat?

Once I get this install completed to my satisfaction, I will be posting detailed instructions for anyone else who wishes to attempt this.

Joshua Diamond
spidey3@mindspring.com

coasTTal

I have the nextel phone and many of the kits that connect to the multipin port on the phone are the same for the i60 and i90.

Also, there was another post of someone installing this same HF kit a couple days ago.

John

TTommyZ

work in the car - I really don't like using a cell phone while driving, shifting, and eating my take out lunch.

JustJeff

I have also found out there is an error to the oft-published <a href="http://home.attbi.com/~woodyb/handsfree/hf1.html">schematic</a>, in regards to the use of the TT/Audi built-in microphone. The TT/Audi built-in mike has a pre-amp on its output that over-drives most OEM hands free cell phone kits. I had struggled with this also, as I tried to over-come this challenge. My adaptaion of this by-passes the <a href="http://home.attbi.com/~woodyb/handsfree/hf4.html">pre-amp attenuation circuit</a>, and wires the mike directly into the cell phones' mike input. Because the on-board, TT/Audi mike's pre-amp needs power, I discovered the schematic error, and I now feed +12V power to this pre-amp mike directly, and take the mike output (amped) directly into the cell phone. This works, with no hard distortion that others have encountered. When I get some more time, I will re-draw this schematic, and fully document my methods.

nikhil

Are you an EE?

JustJeff

Nope, my brother is, I'm just an enthusiast, and know my way 'round electronics

SpideyTT!!!

Jeff -- thanks for the pointer to the power/attenuation circuit schematic. I will be implementing it this way because with the motorola phone I have to use the handsfree kit to get the phone to behave correctly.

Any ideas on how to route the antenna cable, or if I should even bother? I have noticed absolutely no difference in signal strength between using the phone's antenna, the windscreen patch antenna, and the TT's antenna.

SpideyTT!!!

If it works for the V60 kit, it should work for any of the newer Motorola kits, as they all seem to have the same connections.

SpideyTT!!!

Another question:

How well does the dashboard mic work in the roadster when driving on the highway with the top down? The mic from the handsfree kit is basically useless when I drive with the top down, picking up only wind noise (it is mounted near the driver's sun visor).