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guerrison

Solution For Use Of Aftermarket Cd Changer & Ipod?

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Hi,

I've thought of a possible solution to the CD Changer debacle on the LS400 (and possibly other models)- I'd like to run it by the group to see if there are flaws in my thinking.

Whether you're using a Pioneer or Nakamichi Head Unit with CD Changer control the problem is always the same- there are no compatible aftermarket CD Changers. This would be OK if the Lexus replacements didn't cost upwards of $1,000. And if you've just replaced a non-CD Head Unit with one that controls a CD Changer than it's even worse- the wiring to a CD Changer was done at the factory and a custom job would cost $100's.

I've been looking at the wiring schematic for the Head Unit and CD Changer in the Lexus LS400 Service Manual (1991). The Head Unit has ports to the CD Changer for Power +, Power -, Ground, Serial (1), Serial (2), Left +, Left -, Right +, and Right -. My basic idea is to just tap-in any aftermarket CD Changer as long as the CD Changer has a remote. Hook all of the respective ports to the CD Changer, of course ommiting the two Serial connectors. My question is: Would the Pioneer or Nakamichi Head Unit just switch the Left and Right channels 'on' when the CD button is pressed, even though there would be no Serial communication?

If this worked you could mount in the glove box (or trunk, with wiring) one of the many CD Changers (usually RF compatible) which comes with a wired or wireless remote control. Instead of counting on the Pioneer or Nakamichi Head Unit to actually control an original 6-disc Changer you could just use them as a 'line-in' for a self-controlled CD Changer. The possibilities would also include a switcher which would let you change inputs from the CD Changer to say, a hardwired iPod.

I'd like to know if anyone knows, definitively, whether or not the Left and Right audio inputs remain 'on' even if there's no Serial connection. And other thoughts would be welcomed as well.

-Thanks-

Matthew G McNeil

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no that doesnt seem to work. blitzsafe a company with electrical engineers galore have not been able to make it work right. they have made and sold adapters for the lexus and they all havnt worked. tom es300 on this board has spent 100' s of hours trying to get the blitzsafe adapter to work for an mp3 player and it keeps cutting out every 7.5 seconds. it seems the lexus cd changer port with its serial communication lines is not adaptable. if you want to give it a try i have one of the blitzsafe adapters you could experiment with. they made one for nakamichi system and one for non nakamichi. blitzsafe has made hundreds of adapters that work but the one for lexus doesnt.

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That's it exactly. The HU does not enable the CD audio inputs unless it get's a valid, digital data stream on the serial link. Lexus isn't telling and Blitzsafe is just guessing (and guessing wrong).

Tom

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I decided to try to hardwire my mp3 players to my sc400. The idea was much the same one you had. I would tap into the the wires from my CD changer (which does not work). All I was looking for is the CDR-, CDR+, CDL- & CDL+ wires, in order to make a RCA connection that would attach to my RCA to minipin adapter. From there it is just a headphone or base connection away from sound. Since the mp3 players have their own controls all I need is for the CD player to let the signal through. I tapped into the wires by the cd player in the trunk because they were the easiest to get to. If it works I am going to pull out the head unit and tap into the cd player wires from up front.

So far it worked, to a point, I did get a constant signal from two mp3 players. I was able to leave the door of the CD changer open (so it would not try to change cds) and was still able to activate the cd player from the dashboard and keep the music playing through the system from the mp3. However, the signal quality needs improving. Although the HotZip mp3 sounded better than the iPod. The volume on the signal does not seem to be strong enough and if you turn the volume controls all the way up the sound gets distorted. So my next step is to figure out how to get a stronger signal (any suggestions out there?!)

One thing I am going to do tommorrow is to see if the impedence is the same between all of the devices.

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Sorry to hear about your brothers iPod. I live in New York, and believe me I have no intention OF EVER leaving my iPod in my car without me also being in it!

I have found out that you can use the cd changers wires to attach your iPod. You have to leave the cd changer in place so the car will see the cd player and let the signal through. Splice the +, - wires to make rca outputs to connect your iPod to. I just leave the door of the cd player open so it will not try to change any cds, switch to the headunit over to cd and da-da music!

I have found out that by adding a line driver between my iPod and the cd Changer that I get a clear audio. So I got it, I am know able to use my cd changer as my iPod connection. When I get a little time I will make my final install. javascript:emoticon('B)')

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So far it worked, to a point, I did get a constant signal from two mp3 players. I was able to  leave the door of the CD changer open (so it would not try to change cds) and was still able to activate the cd player from the dashboard and keep the music playing through the system from the mp3. However, the signal quality needs improving. Although the HotZip mp3 sounded better than the iPod. The volume on the signal does not seem to be strong enough and if you turn the volume controls all the way up the sound gets distorted. So my next step is to figure out how to get a stronger signal (any suggestions out there?!)

One thing I am going to do tommorrow is to see if the impedence is the same between all of the devices.

Just wondering:

1. what is the CD display showing on the HU when you are playing the mp3 player?

2. What colors are the wires you tapped into on the changer?

3. Was the sound quality descent when you adjusted the volume?

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jw.design,

thanx for the trail blazing! encouraged by your experiences, and armed with instructions on pulling the head unit (http://www.cureline.net/lex/audio/howto_radio_removal.htm), plus the connector and wiring diagrams (http://www.cureline.net/lex/audio/howto_wiring_daigrams.htm), i cut the audio signal wires from the changer and spliced in a 1/8" stereo jack (standard portable audio headphone jack). i don't leave the changer door open, but just let it cycle through the CDs that are loaded. since the changer continues to operate normally (door closed), i will add a switch somewhere near the head unit for switching between the changer and the portable player and plan on using both.

you mentioned adding a line driver -- what make and model did you use?

clearly, the player's headphone and line-out outputs are not well matched to the head's input for the changer. the head and changer are normally connected with a shielded pair for each channel (R+, R-, L+, L-). for this first pass, the jack's common is tied to both R- and L-, +R goes to the right jack wire, +L goes to the left jack wire. did you ever make any measurements of the stock changer to head signals?

thanx again!

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