I actually found a new solution that is easier than relays. I used a AV switch which cost like 4 bucks at Big Lots.

I've read throughout this whole thread. Tons of informative info. Thanks to PureDrifter once again for the write-up.

I tried finding the wiring diagram for the Nak GS4 system but didnt see it posted up anywhere. Do you think you could post it asap?

Also, would you happen to know the location of my amp. I don't want to have to pull things apart to find it.

Thanks again.

I've scanned through the thread and did not notice any wiring information for an SC400. can someone who's done the install help me? I can make the device without a problem, I just need assistance in finding which wires to cut in my 92 SC400.

thanks

anyone? where could i get this information? is there a way I can figure it out ?

I updated the OP with some interesting information i just found.

I discovered that the wiring is different on the 98+ GS/LS Nakamichi systems, the CD changer feeds directly to the headunit instead of going to the amp. the system will work fine but instead of cutting into the harness between the AMP and the CD changer (which wont exist) u need to get the signal between the CD changer and the headunit.

CDR+ B1 Black
CDL+ B2 Blue
CDR- B5 White
CDL- B6 Red

at the CD changer the above refers to the bigger 10pin connector.

CDR- 9 White
CDR+ 10 Black
CDL- 11 Green
CDL+ 12 Red

wiring is for the plug at the cd changer.

see my note on Nakamichi systems, the best place for you to intercept the signal is right behind the cd changer

thank you!!...i just ordered the relays from ebay ($15 for 5). I plan to hook them up next weekend and install an harman kardon drive+play...i'm excited!!!

will post pics once complete

I'm almost done with the install. I do have one question: If I leave the switch on (power going through the relays) will it drain my battery when I turn off the car? I notice when the car is off, I can still run power through the relays. Is this ok?

most likely not but it depends if ur using switched or constant +12v.

mine hasnt and ive left it on overnight before :p (constant +12v)

Thank you very much.

I'll be installing this next weekend :)

Install Complete - much thanks
 

Just a quick note to thank everyone on this thread for a superb instruction set on this mod. I have my 2000 LS400 hard-wired for my iPod and it sounds great!

Couple of notes:

1.) There are two standard ISO 12VDC SPDT relays. This thread uses the the mini, I used the micro. Connectors are tight on the micro, but it's working fine. If you're really on a budget, any junkyard with give you a handful for a few bucks. Google "relay basics" for a wealth of info and pictures of both types.

2.) I could see no reason to attach to the constant 12V power. I connected into the switched 12V ACC for both the relays and the iPod charging. Seems to be OK and I didn't have to worry about disconnecting the battery or the threat of electrical shock. Also, USE a multi-meter to doublecheck yourself BEFORE you cut!

3.) The iPod connector cable from DavidNavone listed in the thread is worth the cost, IMO. Allows for both charging and an additional device on a micro connector.

4.) The Solderless RCA male plugs from Radio Shack are actually the easiest to solder. Remove the center screw and insert your wire, makes it real easy.

5.) I found female disconnects easier to use than soldering to gang the relays together. I just put two wires in each and hopped along until the end for the ground and 12V connections. Again, that's on the Micro relays, the Mini version might have been OK.

6.) The wire harness is very low gauge wire, be very careful cutting back electrical tape. I sliced a wire and had to burn a butt connector to fix.

Guess that's it. Again, much thanks to PureDrifter for a great great thread. And thanks to the authors of the wiring diagrams, made this very eaasy to understand.

My 2000 ES non-Nak system is the same way, I believe. I took off the glove box yesterday and discovered no direct connection between the amp and the headunit.

Based on what I can determine from reading the entire thread I would connect the device between the CD changer and the head unit. Puredrifter, would you be so kind as to confirm this? Thanks.

Finished my install..everyting is working!! thanks Puredrifter!

took me a whole day but i think it came out nicely.

Hear are some pics...

Harman Kardon Drive+Play (hiding wires was a B*tch)..the control unit is installed in the trunk.
http://img155.imageshack.us/img155/4...0104md2.th.jpg

Ipod and switch are hidden...any ideas on how to mount the switch?? this is still a work in progress...
http://img514.imageshack.us/img514/4...0105xi5.th.jpg

anyone know if there is a good switched 12v source in the SC400 trunk near the factory amp / cd changer?