98 Es300 Nakamichi Plays Pioneer Changer Without Wires!

[arriflex]

I'm sorry about the drama in the title, I have been following as many schematics as I can get my hands on. Unfortunately, I have not yet got one for my 98 ES300. However, everything that I find indicates that there are four wires connecting the head unit and the changer which are the pre-amp inputs to the hu. I verified that this is the connector that goes to my changer, which despite my Nakamichi head unit is a Pioneer (is that normal?), and that there are a couple of serial com wires that appear to carry 2.5v, and the usual power lines and ground. Most importantly there are the red, white, green and black wires at pins 1,2,7,8.

This is the amazing part, when I clip those four wires, I still have sound playing with volume control on the head unit. I can still change tracks and discs, I honestly have yet to find what functionality is gone after clipping those four wires! The sound quality is no different whatsoever from what it was before.

Is there a possibility that there is a digital signal or that audio signal is running on one of the 12v wires? I'm not excited about clipping them, but I can easily put an oscilloscope on them to take a look at what is there.

Please explain as this doesn't mesh with everything I've read from my searches here; which by the way, have been incredibly informative, thank you all.

arri

[agentofboom]

I did the same thing and it freaked me out. There aren't enough wires left to carry out serial control data lines, mute, and analog audio.

Might we have a digital i/o?

Im going to give it another go today when i get in to reflow the regulators and amp chip(s). Probably going to add some better cooling too. I can barely finish Dethalbum II without the damn thing muting (thermal protect, i assume) :angry:

[98lexuses300]

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