Ok, 99 XK8, Harmon Kardon system with amp and Changer in the boot. I want to change out the head unit for one that has built in blue tooth for phone and audio streaming, not looking for more power or umph, just better functionality for me. I've read all kinds of threads on audio but haven't found the answer to my simple question: Can I wire an after market HU right to the factory amp, I know it will take a little effort to wire up, but from the dash back can I leave things intact?? Or do I have to also get an aftermarket amp and rewire speakers etc, etc.
Also, if anyone has experience/recommendations on HU for blue tooth streaming I'm looking for suggestions

 

The '98 premium HK system wiring diagram in JTIS shows what appears to be a 6 pin connector with 5 inputs, plus a signal ground and shield at the head unit to the power amp. Some experimentation, cutting the inputs one at a time will probably give you your answer.

One thing for sure though, the connections are not standard RCA plugs.

 

yeah, I assumed it would require butchering some cables, I just didnt know if it somehow tied into some computer or something that would only work with the factory proprietary componants...but what am I saying nothing on these cars would be like that!

 

I do not know for sure on the HK...the successor Alpine does have a data link.

 

I am interested in this also, please keep us posted on your results.

 

Steve...you have the Alpine...it is a different system. The Alpine has a datalink interface to the amplifier.

An interesting question here would be would a new Alpine HU work with the amplifier, because as XKRacer pointed out in antother thread, the new headunits do work with the stock CD changers.

 

I'm rather confused by all of the responses above, but I don't think it's possible to keep the factory amp and install a different head unit. The exception might be if you install another Alpine head unit, but I'm not sure. The factory head unit communicates with the CD changer, nav unit, and amplifier through a cable that contains about 6 wires (I forget the exact number). The cable uses circular connectors and very fine wires on the inside, probably 22 gauge or smaller. If you disconnect the head unit from the amp, then the amp doesn't do anything. I tried playing nav and phone audio through the amplifier with the connector unplugged from the back of the head unit, and it just didn't work. I also tried to bypass the nav unit and play the audio from my Garmin directly through the amp with the comm cable for the nav unit bypassed, but the amp recognized that the nav unit was missing from the loop and didn't play the audio. I also hooked my bluetooth up to the CD changer audio input to the amp so that I can play music from my phone by selecting the CD changer. However, if I unplug the CD changer, the head unit and amp recognize that it's missing and don't allow me to play the bluetooth audio, even though it's hooked directly to the amp.

Sooo... it appears as if the amp, CD changer, nav unit, and head unit are all integrated through the communication cable. If you remove the head unit, the other three quit working.

 

Sam, the original inquiry was on the Harmon Kardon system used from what I believe was '97-'99. On this system the amp is not connected to an Alpine AI-Net like the later ones. It has five inputs and no circular AI-NET connector. Are any of those inputs a datalink? So far no one has chimed in who knows.

 

Thanks for the clarification Steve, I didn't realize HK was for Harmon Kardon. Anyhow, based on what you are saying, it sounds like I am out of luck with my hope that I could install a new HU and only need to tap into the wires in the dash, which was mainly why I was hoping to keep the factory AMP in the trunk in use. My thought was that I don't want to have to run new speaker wires to all of the speakers in the car. I was hoping that behind the current radio I could connect a new system to power, ground, speaker outs etc to the inputs of the factory AMP and all would be happy. I guess not