Does anybody know how the Nakamichi audio system in the early LS400 are wired and if they have an external amp? All the speakers on the right side of my roomate's car went out. We can't tell if its the amp, reciever or speakers.

 

Yes the Nak system has an amp...for the sub, otherwise the power is in the HU. The amp is located in the trunk to the left of the gas tank. Sounds like your roommate's HU is in need of replacement. Here is the definitive source on LS wiring, it's retrodrive's website:

http://www.cureline.net/lex/audio/ho...g_daigrams.htm

 

Is installing an aftermarcket HU in a Lexus hard/expensive to do? I know it should be harder than to put one in my Toyota.

 

It's cake to install an aftermarket HU.

Here's how to do it: http://carstereohelp.com/stereoremovalLexusLS400str.htm

And here's a thread with what you need to buy: https://www.clublexus.com/forums/sho...threadid=94905

It took me about 20-30 minutes to install mine. I did the wiring harnesses inside though. I installed my HU in the middle of a Minnesota winter, it was around 15 degrees...good thing the heater works well! Oh, and you'll probably lose the sub by doing this. I don't think there is a connection for that.

 

the nakamichi had a 5 channel amp in the trunk under the changer. all the info about subwoofer amp and the website wiring diagram in this thread is for the pioneer made lexus premium sound system not the nakamichi made system .