When choosing my screen name I tried to make it easy to remember what vehicle I was talking about when I asked a question. If it don't work, then Hi There! White 1998 LS400, 94K miles, looking to get a tablet (in this case, Android) hooked up to the factory stereo so I can listen to mp3's as I drive. There is a speaker (of sorts) in the android pad, but while there is some fidelity, it is not what one could consider very high. Fortunately for me it appears that the solutions that these guys sell which plugs in (and renders unusable) the CD changer port on the back of the 98-00 radios, and I think it's the same for all of the different Pioneer and Nakamichi units.
https://gromaudio.com/store/bt3_adap...interface.html
Anyone have any experience with these guys? There are several models that they make. This particular unit ($180) can connect phones and pads via bluetooth for wireless streaming and also have a 3.5mm plug for added audio functionality, and other phone oriented stuff.
I do like that it is a plug-in solution that doesn't require any fiddling with the wiring harness other than unplugging the cd changer and replacing it with one of these, and for me the cd changer delete isn't a big deal anyway.

No experience with them, best of luck. All I can contribute here is:

If your car has the touchscreen & navigation, this won't work. AFAIK there are no solutions, the only option is to go full standalone.

I had a similar one of these units in my previous Honda. Had a similar thing, the Honda had a unused AUX port that could be injected into. Routed a 3.5mm cable through the storage cubby next to the gearshift. Worked like a charm. I'm sure modern units with bluetooth also work great. Especially since you retain full OEM function. The volume *** on my DIN sucks.

The basic idea of the Gromaudio must be coming from this.
https://www.clublexus.com/forums/lex...em-stereo.html

It is a good idea to use a CD port. I'd say that Puredrifter's method of above link is quite primitive using 4 relays. I'd use a signal switcher such as a CMOS chip 4066 like this way. The Gromaudio's unit must be related to this method and if it is properly made, it will work.

Wait, that can work for navigation equipped cars? It was my understanding they were fundamentally different because of the special computer running the touchscreen & controls.

Intercepting the CD is truly quite a good idea...

Hi, GROM Audio here
The 1998 Lexus LS 400 is not supported by any of our products, unfortunately. If you go to our website, www.gromaudio.com, there is the search widget that says "Find what fits your car". By using this widget you can check if we have any products that will work with your specific vehicle.

Hi Grom. Thank you for the heads-up. I had originally searched for my 2001 Camry and saw that the same harness was used for both Toyota and Lexus starting in 1998. I extrapolated from that.
By The Way, when I went back to your website just a few minutes ago (6:20pm Pacific time) my browser stopped me from continuing on to your website as the website's certificate expired today. Just so you know.
Back to the CD player input question. I read through some of Pure Drifter's thread and it appears that the CD output was used differently in different generations and with different head units (nakamichi & pioneer, nav and non-nav). I wonder why they decided not to standardize. Probably just to **** us off.
I'm still planning on getting the Grom 3.5mm unit for my Camry as it is listed as compatible. As I recall from a late evening looking at plug diagrams and images of the backs of radio units for the Camry, there is (at least I believe there is) a 12 pin plug on the back of the radio/cassette/single cd unit where a CD changer would plug in if one had been installed. I believe that's where the Grom unit plugs in and I'll be sure to compare the plug for the CD-in port on my '98 LS Pioneer (with nav!) and see what differences there are.
Sorry for causing any confusion.

In ｃase of a JDM Celsior of C model (with a navigation) UCF20/21 manufactured after July 97, there is a way to hook up an external stereo audio signal of L and R. The link below shows where to hook up but the eplanation is written in Japanese. A USDM of a Pioneer navi model probably has a similar board and has the same IC 2068D which is an operational amplifier.
https://minkara.carview.co.jp/userid...ote.aspx#title

Sorry Yamae my Japanese comprehension is non-existent. I'm guessing that the circuit board is in the nav screen control area and not in the hard drive unit in the trunk. I found the arrows and am assuming that those legs of the op-amp are where the +L and +R signal inputs are located, and then just need a ground for the completed circuit. Thank you for the information. Your input is always appreciated.

Thank you for letting us know about our servers, they are fixed now and all is back to normal operations. As of 2001 Toyota Camry, it has the extension port that GROM uses. TOYO is the compatible model. here are the kits that are compatible:
https://gromaudio.com/store/all-toyo.html

400fanboy - I have a Nav equipped car and am currently looking at what are being referred to as Digital Media Receivers as a possible solution to getting digital audio inputs into our cars with the least amount of physical damage while still using the existing amp/speakers/subwoofer, etc. The units that I noticed are single din units that have line outs that should be able to be plugged into the existing amplifiers of our lexus cars, my thinking through the CD input to the amplifier. I suppose it's possible to make a harness to go from the plug that is inserted into the CD player itself but I think it would be easiest to use two channels of whaever output is available at the Digital Media Receiver and run wires down under the passenger seat to the stock amp. The wires then need to be installed into a plug (part # 90980-10799) and plugged into the CD-in port on the amplifier. You would lose the CD changer, or would have to do a Pure Drifter-like switching matrix to keep that functionality.
And of course there is still the need for a "stock" non-nav HVAC control unit. I just purchased one off ebay for $130, and noticed that there were a fair few of them out there.
One downside I can picture would be having two "head units" in the same dash might not be ideal for many people, but since the signal processing (eq, balance, fade) and multiplexing of the speakers and subwoofer are done in the amplifier unit, you still need the pioneer head unit for the controls and control circuits for the stock amp. As an old guy it wouldn't bother me too much as I still have fond memories (well kinda anway) of home stereos with separate tuner, preamp and amplifier stacked one atop the other.
BTW, does anyone know the voltage that the CD player outputs. I looked at the output voltages of two units (an Alpine and a Pioneer) and one was 2v and the other was 4 volts
Thank you aptoslexus for all the wiring diagrams with pinouts and connector shell listings. Invaluable help.

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edit-

Mea culpa - I'm an idiot. I went out and looked at the nav radio "head unit" in the vehicle and realized that all the signal controls for the stereo, fader, bass, treble, probably subwoofer level, radio tuning etc. are not on the front of the nav head unit (as there are on the non-nav pioneer), just volume and some input switching and the cassette player. The control of those signal fuctions must be done using the nav screen. So much for the single din stack idea. Sorry for the misleading idea.
And thanks to Yamae for the helpful link to the amplifier manual. It is quite an interesting unit.

You can download the manual
https://elektrotanya.com/PREVIEWS/39...2066.pdf_1.png
from here.
https://elektrotanya.com/pioneer_lex.../download.html