1999 LS400 Radio Install Questions
09-24-13, 08:38 PM
#16
What head unit, amp and sub are you installing?
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?
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?
For starts, I figured I wouldn't be needing the CD changer anymore, as most of my music is just going to be played off of my iPhone or a flash drive. Basically, what I'm aiming to do is use the new head unit (JVC KW-AV61BT) with the OEM speakers (powered by the OEM amplifier) and the new amplifier (Autotek Mean Machine M4000.1D) and subwoofer (Sundown Audio SD-2 10" 2-ohm DVC).
When it comes to connecting the new head unit to the OEM amplifier, most people suggested soldering RCA cables/connectors to the speaker wire coming from he plugs behind the head unit and then connecting said cables in the corresponding inputs on the new head unit.
The only thing that concerns me now is how I will be able to power the head unit, as that answer seems to be different all across the board.
09-25-13, 04:30 AM
#17
Rookie
Join Date: Jan 2013
Location: TN
Posts: 71
Likes: 0
Received 0 Likes
on
0 Posts
Finding power behind the head unit should not be any problem, I'll check that PDF you posted of the 2000 Pioneer Audio.
IIRC, RCA output from your new head unit is around 2.3V. The speaker level output from your OE head unit is probably higher but this may not be a problem for the OE amplifier, you may just have to turn the volume up a bit more.
Do you have a multimeter? You might could check some of the voltages coming out of your OE head unit. You should be able to do this at the amplifier under the passenger seat.
IIRC, RCA output from your new head unit is around 2.3V. The speaker level output from your OE head unit is probably higher but this may not be a problem for the OE amplifier, you may just have to turn the volume up a bit more.
Do you have a multimeter? You might could check some of the voltages coming out of your OE head unit. You should be able to do this at the amplifier under the passenger seat.
09-25-13, 05:04 AM
#18
Lexus Champion
09-25-13, 07:10 AM
#19
I wish stereo installs were still as easy as they were about 30 years ago when I did my first ones. Now times have definitely passed me by... 
There is an few years old Alpine HU already installed in my newly-acquired 96, but I'm planning to install a newer Alpine CDA-9884 I have just sitting in the garage. I guess I'll have to first see what kind of mess there is behind the current one with the wires and hopefully use this thread as a guide to check everything.
The one weird problem the current HU has is that volume level 1 is decent listening volume when you are driving just by yourself, but when you have others in the car and you want to talk with them, you'd like to turn it down a notch. But all it has is 0 after that...
Hence my question: What should I look for that would cause this when I start the installation of the replacement HU (hopefully this weekend)? Could it be something in the wiring or could it just be the HU itself?
I don't think my car has Nakamichi, nor does it have CD changer, if those would make a difference and there are no aftermarket amps, subs etc. visible anywhere, either.
Sorry for the hijack, OP. I guess I could've started my own thread, maybe...
There is an few years old Alpine HU already installed in my newly-acquired 96, but I'm planning to install a newer Alpine CDA-9884 I have just sitting in the garage. I guess I'll have to first see what kind of mess there is behind the current one with the wires and hopefully use this thread as a guide to check everything.
The one weird problem the current HU has is that volume level 1 is decent listening volume when you are driving just by yourself, but when you have others in the car and you want to talk with them, you'd like to turn it down a notch. But all it has is 0 after that...
Hence my question: What should I look for that would cause this when I start the installation of the replacement HU (hopefully this weekend)? Could it be something in the wiring or could it just be the HU itself?
I don't think my car has Nakamichi, nor does it have CD changer, if those would make a difference and there are no aftermarket amps, subs etc. visible anywhere, either.
Sorry for the hijack, OP. I guess I could've started my own thread, maybe...
09-25-13, 06:02 PM
#20
Rookie
Join Date: Jan 2013
Location: TN
Posts: 71
Likes: 0
Received 0 Likes
on
0 Posts
I went much more overboard back in the early 90's building huge bandpass enclosures and running 3 or more amps. I definitely got that out of my system and will be doing much simpler builds from here on out.
There is an few years old Alpine HU already installed in my newly-acquired 96... one weird problem the current HU has is that volume level 1 is decent listening volume when you are driving just by yourself, but when you have others in the car and you want to talk with them, you'd like to turn it down a notch. But all it has is 0 after that...
09-25-13, 06:03 PM
#21
I wish stereo installs were still as easy as they were about 30 years ago when I did my first ones. Now times have definitely passed me by...
There is an few years old Alpine HU already installed in my newly-acquired 96, but I'm planning to install a newer Alpine CDA-9884 I have just sitting in the garage. I guess I'll have to first see what kind of mess there is behind the current one with the wires and hopefully use this thread as a guide to check everything.
The one weird problem the current HU has is that volume level 1 is decent listening volume when you are driving just by yourself, but when you have others in the car and you want to talk with them, you'd like to turn it down a notch. But all it has is 0 after that...
Hence my question: What should I look for that would cause this when I start the installation of the replacement HU (hopefully this weekend)? Could it be something in the wiring or could it just be the HU itself?
I don't think my car has Nakamichi, nor does it have CD changer, if those would make a difference and there are no aftermarket amps, subs etc. visible anywhere, either.
Sorry for the hijack, OP. I guess I could've started my own thread, maybe...
There is an few years old Alpine HU already installed in my newly-acquired 96, but I'm planning to install a newer Alpine CDA-9884 I have just sitting in the garage. I guess I'll have to first see what kind of mess there is behind the current one with the wires and hopefully use this thread as a guide to check everything.
The one weird problem the current HU has is that volume level 1 is decent listening volume when you are driving just by yourself, but when you have others in the car and you want to talk with them, you'd like to turn it down a notch. But all it has is 0 after that...
Hence my question: What should I look for that would cause this when I start the installation of the replacement HU (hopefully this weekend)? Could it be something in the wiring or could it just be the HU itself?
I don't think my car has Nakamichi, nor does it have CD changer, if those would make a difference and there are no aftermarket amps, subs etc. visible anywhere, either.
Sorry for the hijack, OP. I guess I could've started my own thread, maybe...
09-25-13, 08:43 PM
#22
Actually took a shot at it today and and wish I didn't...
Not sure what I did, but now even the old one is not powering up, even though I hooked each wire the same way they came out.No, it's not the fuse as there is still power coming to the wires (measured with my multimeter). Didn't have too much time to trouleshoot it properly, so I guess I'll wait until the weekend to try to figure everything out.
The wires were quite a mess after who ever installed the current HU, so no wonder something came up...
09-25-13, 08:53 PM
#23
Anyway... Back then you really didn't have to worry about the OEM being too complicated etc. And neither were the systems, really: just the HU, maybe an equalizer somewhere in there if you were trying to be fancy and four speakers.And yeah, I'm known to also have used some home speakers a time or two in the past...
09-26-13, 09:56 PM
#24
So... does anybody know any factory wires (preferably by color, too) I could tap for a 12V Constant and 12V Accessory? Perhaps a wiring diagram of the CD changer in the '99 LS' Pioneer Premium Sound? My friend and I start tomorrow afternoon at about 12 on the new stereo install haha.
Last edited by Sc0pe; 09-26-13 at 11:06 PM.
09-27-13, 06:53 PM
#25
So... does anybody know any factory wires (preferably by color, too) I could tap for a 12V Constant and 12V Accessory? Perhaps a wiring diagram of the CD changer in the '99 LS' Pioneer Premium Sound? My friend and I start tomorrow afternoon at about 12 on the new stereo install haha.
Right now the radio is powered up, grounded and the antenna is hooked up. That's it. I don't know where the speaker wires are and I need your help! Pictures of the radio plugs/colors of the wire will be up in the next hour or so. Car is a '99 LS with Pioneer Premium Sound.
09-30-13, 12:05 AM
#26
Well guys, I figure I'd clean up the post a little bit. So far, I completely abandoned the idea of RCAs and just bypassed the factory amplifier so now the speakers are all hooked up/functioning and confirmed with the fader. Only issue with the speakers is an overall flat-sound which I've narrowed (no pun intended) down to the head unit being powered off of the ridiculously thin factory wire (any possible alternative wires?) but have compensated for it with some mild EQ adjustment.
Now I'm at the amplifier/subwoofer install. So far, I've removed the glovebox and routed my RCA/remote wire through it and down through the side sills and I'm holding off on getting it into the trunk until I have a proper drill (we have a distinct lack of [quality] tools at my house).
The other issue is my power/ground cable - I managed to crimp and solder(?) one end of my power wire but I wasn't able to get a ring terminal on my ground wire, or wherever else it may be needed. You guys know anywhere that might be able to crimp some heavy gauge cable for a reasonable-to-free price? Again, I could do it, but I lack the proper tools.
Now I'm at the amplifier/subwoofer install. So far, I've removed the glovebox and routed my RCA/remote wire through it and down through the side sills and I'm holding off on getting it into the trunk until I have a proper drill (we have a distinct lack of [quality] tools at my house).
The other issue is my power/ground cable - I managed to crimp and solder(?) one end of my power wire but I wasn't able to get a ring terminal on my ground wire, or wherever else it may be needed. You guys know anywhere that might be able to crimp some heavy gauge cable for a reasonable-to-free price? Again, I could do it, but I lack the proper tools.
Last edited by Sc0pe; 09-30-13 at 12:09 AM.
09-30-13, 03:07 AM
#27
Lexus Champion
surprised you guys who are planning a major stereo install or upgrade, don't take 2 minutes and $39 and find the original book of Lexus factory wiring diagrams on ebay or at Faxon Auto Literature and order that up at the same time you are ordering all of your new sound system components, would make the install SOOO much easier to figure out!
09-30-13, 06:25 AM
#28
Rookie
Join Date: Jan 2013
Location: TN
Posts: 71
Likes: 0
Received 0 Likes
on
0 Posts
I've been wanting to get one of those, thanks for the link, I just ordered one. Finding '97 LS400 wiring information online is not as easy as other years.
I also wanna figure out how to have my fog lights on with just the parking lights on, no headlights. Running the headlights in fog or with the fog lights on sorta defeats the purpose of running fog lights at all. Different pattern, aimed lower so as to not reflect off of the fog, DUH! I'm sure there may be some laws about it but I rarely see the PoPo early in the morning on my way to work when I encounter fog.
I also wanna figure out how to have my fog lights on with just the parking lights on, no headlights. Running the headlights in fog or with the fog lights on sorta defeats the purpose of running fog lights at all. Different pattern, aimed lower so as to not reflect off of the fog, DUH! I'm sure there may be some laws about it but I rarely see the PoPo early in the morning on my way to work when I encounter fog.
09-30-13, 09:59 AM
#29
I've been wanting to get one of those, thanks for the link, I just ordered one. Finding '97 LS400 wiring information online is not as easy as other years.
I also wanna figure out how to have my fog lights on with just the parking lights on, no headlights. Running the headlights in fog or with the fog lights on sorta defeats the purpose of running fog lights at all. Different pattern, aimed lower so as to not reflect off of the fog, DUH! I'm sure there may be some laws about it but I rarely see the PoPo early in the morning on my way to work when I encounter fog.
I also wanna figure out how to have my fog lights on with just the parking lights on, no headlights. Running the headlights in fog or with the fog lights on sorta defeats the purpose of running fog lights at all. Different pattern, aimed lower so as to not reflect off of the fog, DUH! I'm sure there may be some laws about it but I rarely see the PoPo early in the morning on my way to work when I encounter fog.
