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Hi All,
I have successfully wired in an aux 3.5mm audio jack to a first gen LS400 Pioneer head unit via the AM/FM radio audio circuit.
When a music source is connected to the 3.5mm jack, the audio is played together with the radio on both AM or FM channels. To fix this I simply cut the audio channels on the printed circuit board for the AM radio (I don't listen to AM!) so that there is no longer any AM audio signal being fed to the processor.
Therefore, this method converts the "AM" button on the head unit to effectively become the "AUX IN" function.
Here is how I did it:
Original Pioneer LS400 Stereo Remove the upper AM/FM circuit board from the radio
Locate TUR and TUL audio circuits
Solder in your Left and Right audio circuits of the 3.5mm audio jack to TUL and TUR circuits.
Connect the ground wire to a ground point on the PCB (grey wire in pic).
Locate AM audio circuits AMR and AML.
Cut the tracks on the PCB using a knife to create an open circuit.
AM radio audio will no longer play through the stereo system.
After carrying out these small modifications simply reassemble the head unit and refit back into the dash. Route your new auxilary cable to your preferred location, select AM and connect your music player.
which I plugged into the cd changer port on the back of the stereo, but I found that the sound was way quieter when compared to just using the stock radio. Would this method fix that problem? Thank you!
Also if I dont use my CD player at all -- I can just hook RCA cable and connect to BT adapter and stream wireless right? @zazzn@- V - -- would this work for 98 LS400 with Navi as well
Is there an issue just getting a nice double din Pioneer to install? I read you lose some oem functions (i think sub?) but I’m not sure if it matters much at all?
Is there an issue just getting a nice double din Pioneer to install? I read you lose some oem functions (i think sub?) but I’m not sure if it matters much at all?
Mine has Navi. I guess I will lose AC controls and a whole lot of stuff.
Also if I dont use my CD player at all -- I can just hook RCA cable and connect to BT adapter and stream wireless right? @zazzn@- V - -- would this work for 98 LS400 with Navi as well
I don't know for certain since i have an SC400 but i dont see why it wouldnt work. You'll just have to find the sound channel wires that run from the cd changer to the headunit. I also recommend doing an aux jack and then attaching something like the Kinivo BTC450 to it. Thats the setup i have and it works perfect. But again this is in an SC400 not an LS.
Also if I dont use my CD player at all -- I can just hook RCA cable and connect to BT adapter and stream wireless right? @zazzn@- V - -- would this work for 98 LS400 with Navi as well
that looks like it will work, but that’s the hard way of doing things. Since this was started lots has changed in the world of parts. I was able to modify my deck to accept aux via the test outputs on my sc300. But in your case there is something even easier, there is a little 30$ unit on eBay that allows you to plug into the back of the deck were a cd changed would go and give you aux. It’s way easier than messing with relays, and then you can attach a Taotronic Bluetooth to aux adapter. Trust me I teses 5 units and the taotronic was the only one which didn’t need a ground loop isolated and didn’t introduce static or kill the bass because of the ground loop isolator.
that looks like it will work, but that’s the hard way of doing things. Since this was started lots has changed in the world of parts. I was able to modify my deck to accept aux via the test outputs on my sc300. But in your case there is something even easier, there is a little 30$ unit on eBay that allows you to plug into the back of the deck were a cd changed would go and give you aux. It’s way easier than messing with relays, and then you can attach a Taotronic Bluetooth to aux adapter. Trust me I teses 5 units and the taotronic was the only one which didn’t need a ground loop isolated and didn’t introduce static or kill the bass because of the ground loop isolator.
Check the back of your radio, if it's a pioneer and it has the standard cd changer port it should work. I got a radio out of a camery and it works. Make sure you get the lexus one though becuase the pinout is diff between lex and Toyota but they are the same between all Toyotas and all Lexus.
I don't know for certain since i have an SC400 but i dont see why it wouldnt work. You'll just have to find the sound channel wires that run from the cd changer to the headunit. I also recommend doing an aux jack and then attaching something like the Kinivo BTC450 to it. Thats the setup i have and it works perfect. But again this is in an SC400 not an LS.
Hey V, this is an old thread, but did you end up figuring out your wiring for this?
that looks like it will work, but that’s the hard way of doing things. Since this was started lots has changed in the world of parts. I was able to modify my deck to accept aux via the test outputs on my sc300. But in your case there is something even easier, there is a little 30$ unit on eBay that allows you to plug into the back of the deck were a cd changed would go and give you aux. It’s way easier than messing with relays, and then you can attach a Taotronic Bluetooth to aux adapter. Trust me I teses 5 units and the taotronic was the only one which didn’t need a ground loop isolated and didn’t introduce static or kill the bass because of the ground loop isolator.
Did anyone ever try this? I too have a '98 LS400 with navigation/Pioneer. Would love to add Aux In, preferably with less effort than the original post indicated. But both of the parts Zazzn linked have disappeared from amazon, and I see no Aux adapter anywhere showing compatible with LS400 (there are several for LS430 and LS460).
Is the OP still the 'state of the art' for this capability?
Did anyone ever try this? I too have a '98 LS400 with navigation/Pioneer. Would love to add Aux In, preferably with less effort than the original post indicated. But both of the parts Zazzn linked have disappeared from amazon, and I see no Aux adapter anywhere showing compatible with LS400 (there are several for LS430 and LS460).
Is the OP still the 'state of the art' for this capability?
I did this on my 98 w/ Pioneer and no NAV and it worked (with a small caveat). Like you, I was unable to find any option that's plug and play.
For my setup, I followed OP's wiring as he also has a 98 non-nav, pioneer system. I don't have a need for the CD changer so instead of using the relays to go back and forth between the Bluetooth input and the CD changer, I just hard wired my bluetooth adapter to the plug going into the amp (as shown in OP's original post). I did what zazzn said to do here:
Originally Posted by zazzn
Jhmkmacool,
This unit is very simple. you don't need the relays if you don't want your cd changer to work, just cut the wires, needed and hook them up to the RCA to 3.5 cable.
Then you can an AD2P BT adapter to stream music or get something like airenabler to stream via airplay, over wifi if you have IPhone. WIFI is lossless, so no worries there!
Basically all this whole thing does is change the source from the audio back into the deck from the CD change to your AUX cable (which can be adapted to a Bluetooth receiver).
It works great and has crystal clear quality but I can't listen to any other sources (AM/FM/Tape) unless my bluetooth adapter is powered off. The signal from the adapter seems to be overtaking all input sources (I can hear my bluetooth audio from AM, FM, Tape, and CD). Interestingly, it's not totally disabling those sources, though, because I can hear audio from the AM and FM radio when I turn the volume way up and have nothing playing on bluetooth.
I have not investigated further but the easiest fix would be to add a toggle for power to the bluetooth adapter. I'd prefer not to do that but without a proper wiring diagram I can't fully understand what might be going on.
I did this on my 98 w/ Pioneer and no NAV and it worked (with a small caveat). Like you, I was unable to find any option that's plug and play.
It still sounds like a lot of work, and I do like to use the radio as well as bluetooth. I think I'll stick with the FM transmitter in the cigarette lighter - not quite the same sound quality, but good enough.
Hi there, I found this post through a Reddit post on how to wire up a Bluetooth adapter under the seat for 98 non nav non Nak LS400s, but I keep finding images of the wiring that don't match my 1997 factory amp. I have four plugs, left to right: white, gray, green, orange. What does each of these plugs do? I believe I'm supposed to tap into the CD input but all of the pinouts I've found online seem to gloss over which of those wires it might actually be.
