Ok sweet thanks. Anyone have any idea how he did that? I read it and still dont understand hehe.

 

You'd think that somebody would make an aftermarket kit that plugged into the molex connectors. I think I'd buy one.

As explanation, it appears that he wired in a toggle switch so that the Lexus' amplifier input can be switched either from the radio head-unit or the Ipod. The PIE isolator device is needed to convert from the Ipod's unbalanced output to the Lexus' balanced input.

So, it appears the Ebay guy was maybe on the level after-all, albeit with maybe less than clear directions.

 

Ok from the lexus tech sheet I have the 4 wires from the radio to the amp are as follows:

Black: L-
Yellow: L+
Blue: R-
Red: R+

Pink is the TX+ and tourquise is TX-, that should be all we need. I have not verified the colors of these wires since it is dark outside and I don't have a garage but if all we need todo is tape those wires then we may be able to get this working in the rx300. Anyone else out there with light wanna give it a go? If I get time tomorrow ill play around and see what I can get going.

 

From Ipod create L-/L+ and R-/R+
Can be done by centertapped audio transformer [use to be very common with tube amps]. If you can get a gain any where around 2 it would be great [see my findings about actual level match].
Incendtally you will connect to the ceter tap to "signal ground" line in the RX audio wiring harness. [If this does not make sense to you, I strongly urge you to STOP and not to proceed]

The switches essentially connect the signal out-put from the ipod set up OR the cd player to the
amplifier.

Switch1 (dble pole dble throw)
audiotrans L+ ----------
........................................... ------- Head Unit L+
.................... cd L+ ------- /

audiotrans L- ---------
........................................... ------- Head UNit L-
..................... cd L- ------- /


Switch 2 (dble pole dble throw)

Same as above but replace "L" with "R".

[Note: Switch shown in CD source select]

Disclaimer: No gaurantees and if you damage your equipment/vehicle, you are on your own.

Salim

 

If you know the Serial Control protocol used by Lexus, please share. Otherwise the TX signals should be left alone.

Previous post only deals with routing audio signals with volume-tone controls via Lexus head unit.

Salim

 

Is this what I would need? http://www.radioshack.com/product/in...tId=2103254&cp also I was thinking of tapping in right at the amp (which is supposed to be in the trunk and I cant find it), because I wish to use this with my car pc. Would tapping into it at the amp work? Also from what you wrote it looks like you are going in from the cd changer side is that what I should do? Attached is a picture from alldata, cleaned up a bit to show only what we need, anyway someone can show me visually what needs to be connected?

 

Ckt I am building will go through the pre-amp of the HU [nano ipod line level out .. will require volume control and tone controls].

For audio transformer please check to make sure your ipod can drive in (without shorting out) and the gain [turn ratio] needs to be close to get a signal level match [ipod level vs CD level]. By looking at the picture the transforme looks ok but check the electrical characteristics. SeattleCone used an isolating transformer ... see his note. Also the ipod body ground is signal ground. You may like to electrically isolate the metal ground of ipod from the RX.

I have not explored the direct amp input [not even sure if it requires a differential input from head unit and never mesaured the signal level.

What you should do is your call. Apparently I have provided the rope and can only hope you make the right choice. My reccomendation to others would be ... fm-transmitter or tape-in.

Note: The incomplete project I am undertaking uses opamps instead of isolating transformer and relays for swithes. I had to go through lot of trouble tapping out signals without destroying the harness in the SC. It has been a money pit for me and still lying on my kitchen table. The SC is all buttoned up.

Salim

 

Any more progress on this?
I want to do this to our '99 RX300.

From the thread " Adding audio input to SC430 for MP3 or satellite radio, some success at last"
There is a link to a PIE module that automatically switches input when a primary device is detected.
http://www.myradiostore.us/noise-fil...rs/mpss-2.html

From the description, if you make the iPod your primary device, when it is powered on and sending a signal, the signal is switched to it. When the iPod is powered off, the signal is switched back to the head unit.

Also, I have a CD changer.. Is there a way to use the wires from the changer unit? With an iPod, I don't use it anymore so I would be fine losing it.

thanks.

 

Here is a link to what I did

https://www.clublexus.com/forums/sho...d.php?t=206797

Right now I am sitting on the fence as I have not found a resonable plug and play soluiton for all types of Lexus (older version) [To be exact not even for one model]. What I did for my son's SC was way too painful. Producing the circuit in a packaged form is not a problem. Real estate and cost goes down if the CD input is cut for ever.

Hopefully soon soon I can look for volanteers who are willing to review and cut open their vehicle to splice-in the aux-input.

Salim

 

With my car pc I wont even be using the cd changer at all. If you could make me a splice in auxin for my rx300 I would gladly pay you

 

Please use PM if you are willing to splice-in.

Salim

 

Does the changer need to still be connected and spliced in? Or could I simply remove the connector and tap into the connector ends? I've done this with other applications and it works great and allows me to simply plug it back in when selling the car.

 

Folks:

Since I am contemplating the thought of proto-typing this product, I think it becomes in-appropriate to discuss it on the forum. PM (private mail) is more appropriate for person to person communication.

On the other hand I will gladly assist/answer questions as long as they are general in nature and are benifitial to all subscribers.

Other than the audio signals, Lexus uses serail communication protocal between units. Notice how radio turns on when CD goes in-active (like eject cd). From my understanding of the system, CD needs to remain plugged in, and one feeds the audio from another source.

If my undesrstanding is wrong please post.

Salim

 

If both (male and female) connectors are available, one can make a plug and play harness.

Salim

 

Here's another good tutorial.. It's for an IS300.

http://my.is/forums/showthread.php?t...0&page=1&pp=30

The 14-pin screw socket terminal socket for the 4PDT relay is a nice addition for easier installation.

I haven't found too many post about success with the mpss-2 http://www.logjamelectronics.com/piempss2.html

but a I have found a couple of people that say it work.