1999 LS400 Radio Install Questions
#1
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Background
So I'm planning on installing my head unit/amp/sub myself (with the help of a buddy or two) in my 1999 LS400 with OEM Pioneer/Lexus Premium Sound and I've been heavily researching the subject checking out wiring diagrams and what not for the past week. Also, this is my first time touching car audio (can't really say the same for the buddy or two I mentioned earlier) so please don't hurt my feelings too badly.
Problem
So I've noticed a few things that are either hazy or not mentioned at all in the the various threads/diagrams/etc. that I've been checking out around the forum and the internet in general.
Questions
1. Dimmer wires - Since they don't seem to exist as for as the 98-00 models go, what are some suitable alternatives?
2. Illumination wires - There are two different wires which are both labeled as ILLUM in the wiring diagram I linked. Could I use either one?
3. Antenna wires - So there are ~3 antenna wires based on the following diagram (attached below) labled ANT, ANTA, ANTB. Which do I use for the head unit? I have a 99.5% feeling that I'm going to need an antenna adapter so any ideas on that?
4. Speaker wiring - Okay, I'm completely lost here. How would I go about wiring the speakers so that they ran off of the head unit and completely bypass the amp?
5. Reverse wire - I'm not installing a reverse camera during this install but plan on it in the future. Should I tap the wire now, or just wait? And if so, then which wire should I tap into?
6. Power wire - Are there any wires in the car that I can use to power the head unit? I remembered someone mentioning the power for the OEM CD changer awhile back. Would that work?
7. Soldering in the car - Is there any way to avoid it? Or is it pretty much inevitable?
So I'm planning on installing my head unit/amp/sub myself (with the help of a buddy or two) in my 1999 LS400 with OEM Pioneer/Lexus Premium Sound and I've been heavily researching the subject checking out wiring diagrams and what not for the past week. Also, this is my first time touching car audio (can't really say the same for the buddy or two I mentioned earlier) so please don't hurt my feelings too badly.
Problem
So I've noticed a few things that are either hazy or not mentioned at all in the the various threads/diagrams/etc. that I've been checking out around the forum and the internet in general.
Questions
1. Dimmer wires - Since they don't seem to exist as for as the 98-00 models go, what are some suitable alternatives?
2. Illumination wires - There are two different wires which are both labeled as ILLUM in the wiring diagram I linked. Could I use either one?
3. Antenna wires - So there are ~3 antenna wires based on the following diagram (attached below) labled ANT, ANTA, ANTB. Which do I use for the head unit? I have a 99.5% feeling that I'm going to need an antenna adapter so any ideas on that?
4. Speaker wiring - Okay, I'm completely lost here. How would I go about wiring the speakers so that they ran off of the head unit and completely bypass the amp?
5. Reverse wire - I'm not installing a reverse camera during this install but plan on it in the future. Should I tap the wire now, or just wait? And if so, then which wire should I tap into?
6. Power wire - Are there any wires in the car that I can use to power the head unit? I remembered someone mentioning the power for the OEM CD changer awhile back. Would that work?
7. Soldering in the car - Is there any way to avoid it? Or is it pretty much inevitable?
Last edited by Sc0pe; 06-28-13 at 03:14 PM.
#3
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My audio days have long past, FWIW, much of the factory harness will not carry-over to the new head unit. Most you will be able to use with some testing is: switched power, hot, ground and antenna leads.
1-2. Dimmer/illumination wires, unless the spec on your head unit allows this, it's gone.
3. For varying reception the factory antenna leads would lower or retract the antenna partially. In the case of your new unit, the ones I had used only have one antenna out so you'll need to figure out which one fully extends the antenna or allows sufficient reception partially extended.
4. You can trace the wiring diagram but I would run fresh.
5. Tap the appropriate wire. However if you run a relay from the back-up lights or similar reverse activated line, make sure it has sufficient power to properly run the camera.
6. Head unit power can be run from any switched source on that circuit provided it has sufficient rating.
7. What would you solder? In my days, we used taps/splices for remote lower power functions. High draw lines were dedicated. When it came to speakers always a clean straight run.
Others can chime, I'm pretty rusty with audio these days.
1-2. Dimmer/illumination wires, unless the spec on your head unit allows this, it's gone.
3. For varying reception the factory antenna leads would lower or retract the antenna partially. In the case of your new unit, the ones I had used only have one antenna out so you'll need to figure out which one fully extends the antenna or allows sufficient reception partially extended.
4. You can trace the wiring diagram but I would run fresh.
5. Tap the appropriate wire. However if you run a relay from the back-up lights or similar reverse activated line, make sure it has sufficient power to properly run the camera.
6. Head unit power can be run from any switched source on that circuit provided it has sufficient rating.
7. What would you solder? In my days, we used taps/splices for remote lower power functions. High draw lines were dedicated. When it came to speakers always a clean straight run.
Others can chime, I'm pretty rusty with audio these days.
#4
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My audio days have long past, FWIW, much of the factory harness will not carry-over to the new head unit. Most you will be able to use with some testing is: switched power, hot, ground and antenna leads.
1-2. Dimmer/illumination wires, unless the spec on your head unit allows this, it's gone.
3. For varying reception the factory antenna leads would lower or retract the antenna partially. In the case of your new unit, the ones I had used only have one antenna out so you'll need to figure out which one fully extends the antenna or allows sufficient reception partially extended.
4. You can trace the wiring diagram but I would run fresh.
5. Tap the appropriate wire. However if you run a relay from the back-up lights or similar reverse activated line, make sure it has sufficient power to properly run the camera.
6. Head unit power can be run from any switched source on that circuit provided it has sufficient rating.
7. What would you solder? In my days, we used taps/splices for remote lower power functions. High draw lines were dedicated. When it came to speakers always a clean straight run.
Others can chime, I'm pretty rusty with audio these days.
1-2. Dimmer/illumination wires, unless the spec on your head unit allows this, it's gone.
3. For varying reception the factory antenna leads would lower or retract the antenna partially. In the case of your new unit, the ones I had used only have one antenna out so you'll need to figure out which one fully extends the antenna or allows sufficient reception partially extended.
4. You can trace the wiring diagram but I would run fresh.
5. Tap the appropriate wire. However if you run a relay from the back-up lights or similar reverse activated line, make sure it has sufficient power to properly run the camera.
6. Head unit power can be run from any switched source on that circuit provided it has sufficient rating.
7. What would you solder? In my days, we used taps/splices for remote lower power functions. High draw lines were dedicated. When it came to speakers always a clean straight run.
Others can chime, I'm pretty rusty with audio these days.
3. For the antenna, any idea on how exactly I would wire up one of those connectors and more importantly, where I could get one?
4. From what I read on some of the threads, people soldered RCA connectors to the speaker wire and just connected that to the back of the head unit. If the RCAs are only signal wire, then how are the speakers being run off of the head unit? The wires on the harness (the one that came with the stereo) are supposedly amplified so I'm confused on that.
6. Do you have any recommendations? I need about 50+ watts going to the head unit since I plan on running the stock speakers off of it.
7. Pretty much just the speaker wire and various harness connections. For any wire tapping, I'll probably use one of the posi-tap connectors.
#5
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UPDATE:
1. [FIXED] Dimmer wire doesn't exist (in the 98-00 LS400s) and isn't really needed.
2. [FIXED] Illumination wire can just be substituted with a wire that comes on with the headlights. (For those that don't know, the Illumination wire will dim the unit when the headlights turn on.)
3. I'm not sure about connecting the antenna to the head unit (my car didn't come with a physical antenna so there shouldn't really be any issues with controlling it to go up/down). Any ideas on an adapter?
4. I'm going to connect RCAs to the speaker wires accordingly and run that into the back of my head unit's RCA inputs so that they are run from the head unit's power and bypass the amp.
5. [FIXED] I'll just do this when I install the camera rather than now.
6. Any ideas on a 12v source to tap off of for the ACC and Constant wires? (Preferably something with more power since I plan on running the speakers off of the head unit itself.)
7. [FIXED] I'll be resorting to crimp connectors for ease of use and then covering with electrical tape so this is no longer a concern.
NOTE: Anything labeled as [FIXED] is no longer an issue. Anything that isn't, however, I could use some help/clarification with.
1. [FIXED] Dimmer wire doesn't exist (in the 98-00 LS400s) and isn't really needed.
2. [FIXED] Illumination wire can just be substituted with a wire that comes on with the headlights. (For those that don't know, the Illumination wire will dim the unit when the headlights turn on.)
3. I'm not sure about connecting the antenna to the head unit (my car didn't come with a physical antenna so there shouldn't really be any issues with controlling it to go up/down). Any ideas on an adapter?
4. I'm going to connect RCAs to the speaker wires accordingly and run that into the back of my head unit's RCA inputs so that they are run from the head unit's power and bypass the amp.
5. [FIXED] I'll just do this when I install the camera rather than now.
6. Any ideas on a 12v source to tap off of for the ACC and Constant wires? (Preferably something with more power since I plan on running the speakers off of the head unit itself.)
7. [FIXED] I'll be resorting to crimp connectors for ease of use and then covering with electrical tape so this is no longer a concern.
NOTE: Anything labeled as [FIXED] is no longer an issue. Anything that isn't, however, I could use some help/clarification with.
Last edited by Sc0pe; 06-28-13 at 03:18 PM.
#6
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i'll try and help here but i have a question. am i correct in assuming you are going to use a single amp for the sub and use the headunit to power the speakers? if so i would simply invest in the beatsonic box so the factory amp is NOT bypassed. this will make running everything so much easier and smoother, esp for a first timer!
3. i'm not sure if the factory pioneer uses a coaxial antenna wire output which should mate to the aftermarket headunit (HU) with no problems. it should just plug right in. since your car is a 98-up you will NOT have a power antenna like us 95-97 folks including RA40, so just ignore the blue "power antenna" wire on your aftermarket HU harness (if it has that feature at all).
4. the RCAs are used to provide signals to the amps, NOT power. if my assumption about your setup is correct, you will only need to run a single RCA set (either SUB out, or REAR out depending on headunit) to the amp to signal the sub. a power wire will need to be run separately for the amp connected directly to the battery with an inline fuse, as well as a ground wire.
6. there should be plenty of 12V sources around the factory wire harness but if you get the beatsonic kit, all the guesswork is gone. i highly suggest you invest in it!
http://www.beatsonicusa.com/beat-sonic-sla-22ad.html
3. i'm not sure if the factory pioneer uses a coaxial antenna wire output which should mate to the aftermarket headunit (HU) with no problems. it should just plug right in. since your car is a 98-up you will NOT have a power antenna like us 95-97 folks including RA40, so just ignore the blue "power antenna" wire on your aftermarket HU harness (if it has that feature at all).
4. the RCAs are used to provide signals to the amps, NOT power. if my assumption about your setup is correct, you will only need to run a single RCA set (either SUB out, or REAR out depending on headunit) to the amp to signal the sub. a power wire will need to be run separately for the amp connected directly to the battery with an inline fuse, as well as a ground wire.
6. there should be plenty of 12V sources around the factory wire harness but if you get the beatsonic kit, all the guesswork is gone. i highly suggest you invest in it!
http://www.beatsonicusa.com/beat-sonic-sla-22ad.html
#7
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I can't really justify a reason for paying $280 for a set of wires, but that's just me.
3. Thank you so much for clearing that up
I wasn't really too sure about that since our cars' audio systems don't really have anything "universal" in them, so to speak.
4. Ah, alright. I was confused on how that all worked. So basically, add RCAs to the signal wires coming from the amp and just run them into the preamp outputs on the head unit? Also, is there any wire I could tap in the trunk for an amp turn-on? Or would I have to run an 18 gauge wire straight to it? And would tapping off of said wire be alright? Like if I were going to tap off of that for the factory amp turn-on?
6. Ah, alright, just to verify, I'm using this wiring diagram from Lextreme. Could I just use the CD changer power wire to power my head unit and use the factory radio ground?
3. Thank you so much for clearing that up
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4. Ah, alright. I was confused on how that all worked. So basically, add RCAs to the signal wires coming from the amp and just run them into the preamp outputs on the head unit? Also, is there any wire I could tap in the trunk for an amp turn-on? Or would I have to run an 18 gauge wire straight to it? And would tapping off of said wire be alright? Like if I were going to tap off of that for the factory amp turn-on?
6. Ah, alright, just to verify, I'm using this wiring diagram from Lextreme. Could I just use the CD changer power wire to power my head unit and use the factory radio ground?
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#8
Lexus Champion
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I am starting to like the option of a new sub amp vs. an overpriced beatsonic when replacing a head unit, better and cheaper if you can do a little DIY labor.
#9
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Also, an extra question - What gauge wire is used in the factory wiring (not speaker wiring but just the factory harness in general)? Is it 16 gauge or 18 gauge?
Last edited by Sc0pe; 06-28-13 at 09:23 PM.
#10
Lead Lap
iTrader: (28)
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The easiest way to find the right wires in the factory harness is to buy an adapter for installing an aftermarket radio into your car. Metra makes these and they cost around $20.00. It plugs into the factory harness and has all the wires labeled for you.
Why would you want to use the factory wiring or speakers anyway? You can do much better and install everything more easily if you avoid the factory system all together.
Send me a PM if you would like to discuss this further.
Good luck!
Why would you want to use the factory wiring or speakers anyway? You can do much better and install everything more easily if you avoid the factory system all together.
Send me a PM if you would like to discuss this further.
Good luck!
#11
Lexus Champion
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run power wire to battery, ground onto the chassis..the steering bar behind the center console. no antenna wire needed if you're 98+. the ACC and illumination is off the factory harness. those are the only two you need off the factory harness. run all the speaker wires off the harness thats connected to the AMP under the passenger seat if you don't need aftermarket speakers. 12 gauge wires is more than you need for all the wires.
#12
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The easiest way to find the right wires in the factory harness is to buy an adapter for installing an aftermarket radio into your car. Metra makes these and they cost around $20.00. It plugs into the factory harness and has all the wires labeled for you.
Why would you want to use the factory wiring or speakers anyway? You can do much better and install everything more easily if you avoid the factory system all together.
Send me a PM if you would like to discuss this further.
Good luck!
Why would you want to use the factory wiring or speakers anyway? You can do much better and install everything more easily if you avoid the factory system all together.
Send me a PM if you would like to discuss this further.
Good luck!
run power wire to battery, ground onto the chassis..the steering bar behind the center console. no antenna wire needed if you're 98+. the ACC and illumination is off the factory harness. those are the only two you need off the factory harness. run all the speaker wires off the harness thats connected to the AMP under the passenger seat if you don't need aftermarket speakers. 12 gauge wires is more than you need for all the wires.
![](http://p.globalsources.com/IMAGES/PDT/B1054641472/Car-Antenna-Adapter.jpg)
#13
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So it's been 3 months now and I am FINALLY going to install my radio/amp/sub (long story, short, I waited a bit because I didn't really have the experience/tools/etc. and a close friend of mine just happens to be available next Friday and he offered to help). At this point, all I'm wondering about are the Metra/Scosche harnesses.
My questions right now are::
NOTE: I have a 1999 LS400 with the Lexus (Pioneer) Premium Sound.
My questions right now are::
- Has anybody had any experience with them?
- Do they plug right up to the factory connectors or am I better off wiring RCAs to the speaker cables?
- Would the wiring be basically the same (I understand the the colors don't match right off the bat, but the wires' purposes remain the same)?
NOTE: I have a 1999 LS400 with the Lexus (Pioneer) Premium Sound.
Last edited by Sc0pe; 09-20-13 at 09:27 PM.
#15
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So it's been 3 months now and I am FINALLY going to install my radio/amp/sub (long story, short, I waited a bit because I didn't really have the experience/tools/etc. and a close friend of mine just happens to be available next Friday and he offered to help). At this point, all I'm wondering about are the Metra/Scosche harnesses.
My questions right now are::
NOTE: I have a 1999 LS400 with the Lexus (Pioneer) Premium Sound.
My questions right now are::
- Has anybody had any experience with them?
- Do they plug right up to the factory connectors or am I better off wiring RCAs to the speaker cables?
- Would the wiring be basically the same (I understand the the colors don't match right off the bat, but the wires' purposes remain the same)?
NOTE: I have a 1999 LS400 with the Lexus (Pioneer) Premium Sound.
How much head unit power do you have?
I'm not sure if the music signal coming from the OE head unit is at RCA level (called line level) or if it is at a higher level (called speaker level).
You might try the RCA connections off of your new head unit first to see what the OE amp wants to see.
If I'm reading the wiring diagram correctly, the OE system is not configured like an aftermarket system is.
-A basic aftermarket system starts with the head unit. You can have things connected to the head unit feeding it signal like a CD changer, iPod etc. The aftermarket head unit is also what is called a pre-amp, it takes all the signal inputs, radio, tape, CD, iPod etc., and sends the one you select at RCA/Line level to the amplifiers or to it's built in head unit amplifier.
-The amplifiers then send amplified signal to the speakers.
HEAD UNIT -> AMPLIFIERS -> SPEAKERS
Whats weird about the OE system is that the CD changer does not connect to the head unit, it connects directly to the amplifier under the passenger seat. This means that the OE head unit is only a radio, tape player and control panel for the EQ, fader, balance and volume. It is just controlling these things which must be inside the OE amplifier, the actual pre-amp stage is inside the amplifier, not the head unit. Otherwise, none of the controls on the OE head unit would do anything to the signal coming from the CD changer, it doesn't go thru the head unit.
Were you planning to still use the OE CD changer? This might get kinda tricky, might be easier to send it's signal to an AUX input on your new head unit if possible.
Anywho.....If you are not gonna use the OE CD changer and want to feed all the speakers off of your new head unit and bypass the OE amplifier altogether that should be doable.
-If you wanted to keep the OE amplifier powering the speakers you would need to connect your new head unit to these 4 wires.
Left Front + Red
Left Front - Green
Right Front + Black
Right Front - White
They should be in the connector behind the head unit, there may be an adapter so you don't have to cut the connector off.
Sorry for the long windedness.
Might you know where I'd find the same radio wiring diagram for my 1997 LS400 non-Nakamichi system?
Last edited by LEXUSA400; 09-24-13 at 02:17 PM.