Well Sports Fans.... 2weeks of study and 8 hours of work and my CK3100 plays throught the car speakers and mutes the radio during a call. 5 different installers refused to wire it in to do that, each wanted to use a #@%?! external speaker. But I was determined. So here's how I did it.
First, there's a difference between an SC430 with Nav and without. The left hand speaker wire you'll need comes from the radio amp if your car doesn't have nav and from the nav amp if it does.
Basically, you need to route the speakers through the black, in-line, device of the Parrot kit and use the yellow mute line that comes with it.
On the parrot kit, clip the power cable (12V, ignition and ground) with fuse holders off the wire harness it comes on. Throw away the rest of the harness, it's not for our car.
You can pick up power and ignition from connector R3 (closest to driver side (US)) behind the radio. R3 is a 20 pin connector. Pin 1 is top row and pin 11 is directly under it in the bottom row. Pin 11 is "acc" (ignition) a gray wire and B+ is pin 1 a white wire with a red stripe. Ground can be pick up from the chasis.
Next, you need to interupt the speaker signal, route it through the black box on the wire harness and back to the speakers. On the CK3100 there is a male and female plug on that harness. The male side goes to the speaker, the female side goes to the amp. You have to cut the wire coming from the amp and feed the signal to the parrot harness and then to the speakers. In the Parrot wire harness Green and Blue wires are used for the Right Front speakers (green is + and blue is -). Orange and Red are used for the Left Front speakers (Orange is + and Red is -).
I created a bundle of 9 wires and snaked them throught the center consol under the read seat (which, by the way, is easy to remove) through an existing hole in the rear wall to the amps I needed to get to.
You'll have to remove most of the trunk padding, the nav unit with it's amp attached and the radio amp. I'm assuming most people interested in this project don't have the Lexus cellular phone installed. If you do, you must take that into consideration and the wiring probably changes. See http://techinfo.lexus.com ($10 per day) for your wiring diagram.
The Mark Levinson amp in my car has two connectors in the back, S22 and S23. you need to get into the wires of S23. S23 is a 25 pin connector that moves the audio signal from the amp to the speakers and also carries the Telephone mute signal to the amp. Pins 1 (top row) and 14 (bottom row directly beneath it) are the right door speakers. I cut the wires about 2 inches from the connector so I had enough room to solder to both sides of the cut. Pin 1 is +, a blue wire with a black stripe and Pin 14 is -, a blue wire with a red stripe. I wired the amp side to the blue and green wires I cut off the female connector of the Parrot.
The left hand speaker lines don't come from the radio amp. They come from the nav amp. So I had to open the harness going to connector N6 ( a 12 pin connector attached to the nav amp which sits on top of the nav unit computer. Only a single connector goes to the amp. Pins 1 and 6, brown and green wires respectively, go to the driver's side door speakers. Pin 1 (brown) is + and Pin 6 (green) is -. Again I cut the wire so I could solder on both sides of the cut. Amp side goes to Orange and Red of the female connector in the Parrot kit and the speaker side went to the Orange and Red of the male connector.
Lastly was the mute line. The yellow (single mute) wire coming from the little black box on the Parrot wire harnes goes to Pin 3 of S23 on the Radio amp. Since that line is the telephone mute line and my car doesn't have the Lexus phone, I just cut the red and black wire on pin 3 and connected the yellow mute line to connector side of the cut and left the other end free.
Then I had to put the car back together. Just a reminder. Disconnect the negative battery terminal before you start working. when you reconnect it the only thing i had to do was reset the memory seats and all that requried was to move the seat forward all the way until it "beeps" then tilt the seat back all the way up until it "beeps" and then you can adjust the seat and set the memory.
The Parrot works flawlessly! I use a Treo 650 and when I call out or a call comes in the radio mutes completely and the phone plays throught the door speakers. When the call is over the radio returns seamlessly.
I understand why installers want to use the little "junky" external speaker.... it's too much work for them to do it right. But remember, NOTHING IS TOO MUCH FOR A FANATIC! And so my saga. I hope it is helpful to others who, like me, couldn't find instructions anywhere to do this.
DISCLAIMER..... I spent all day and got it to work. I make no promises or representations that it will work on your car. Good Luck. Rich
