Sceptre

iTrader: (2)

First off, use the information at your own risk. I’m not responsible if you screw up your car. I’m not an engineer, or a professional. I just do this as a hobby.

Secondly this is not meant to be a comprehensive DIY how to. Just some tips and info on what I did. Also I installed this in 2009, so it has been 3 years, but since there is not a lot of info for us folks with Nak system to aftermarket . . . . here is what I did.

My car is a 2000 GS300 with the Nakamichi system. I installed a Pioneer AVIC-D3 w/ Bluetooth in it. My subwoofer is not connected. I could probably figure it out, but never got around to it. Also the amp is in the trunk, not behind the glove box like the non-naks.

You will need the METRA Toyota harness (or any aftermarket 87+ toyota) to route to the speakers. Looks like this



So basically, you are going to bypass the amp in the rear. So instead of running new wires to the speakers in the door, you are going to take the Toyota harness plug it into the stock radio plugs. DO NOT CONNECT IT TO THE AFTERMARKET HEADUNIT YET.

You will only be using these Metra harnesses for speaker ONLY.

So the Front right +/-, Front left +/-, rear right +/- and rear left +/-. A total of 8 wires you LATER directly connect to your new HU harness. Write down the corresponding wire color. (ie – From the Metra harness, it should say which is FR+, FR-, RR+, RR- etc . . . plug it in, look at the corresponding stock wire color.

It should be

(on the small plug)
RR+ = Red
RR- =Green
RL+ = Black
RL- = White

(On the big plug)

FR+ = Light Green
FR- = Purple
FL + = Pink
FL- = Orange

It should look something like this



Now go to the trunk, under the right side of the floor, remove the cover and you will see the amp. There are 4 plugs on the left side of the amp. Unplug all 4 plugs. Tape up the grey and orange plug. You will not use those anymore.

SIDEBAR: This is the point of no return. You will be cutting wires off the white and green harness plugs. I left like 1.5 inches of wire when I cut it off the harness just incase I want to go back, to stock, but realistically, it would be a PITA.

The white plug is the input wires from the head unit. Those wire colors will correspond to the ones mentioned above.

On the green plug, this is going to the speakers, The color is as follows

FL+ = Pink
FL- = Purple
FR+ = Light Green
FR- = Blue
RR+ = Red
RR- = White
RL+ = Black
RL- = Yellow

So now you connect the colors from the white plug to the corresponding one on the green plug.

So
GREEN----WHITE
FL+ = Pink----FL + = Pink
FL- = Purple----FL- = Orange
FR+ = Light Green---FR+ = Light Green
FR- = Blue----FR- = Purple
RR+ = Red----RR+ = Red
RR- = White---RR- =Green
RL+ = Black----RL+ = Black
RL- = Yellow----RL- = White

(Updated thanks to Moneybagz)

Once connected, it should look something like this.






There should be 3 extra wires on the white plug that you will not use.

NOW the reason you did not connect the metra harness to the aftermarket headunit is so you can now test your connections. Take a double A battery and place the RR+ (Purple) on the positive end and the RR- (purple / Black stripe) on the negative end of the Metra harness, and listen for the speaker to crackle. That is how you know that the speaker is connected. Be careful not to blow your speakers.

Now to connect the other wires.

12v (ignition) = Grey
Constant (Battery) = Blue/yellow
Negative (Ground) = Brown (I actually did not use this one, but instead connected directly to the metal bracket in the side)
Illumination – Green wire on the orange plug
VSS – purple wire on blue plug under the driver side (see picture below)



Good luck,

LudeNsoL

iTrader: (14)

Awesome thank you!

rome58

Great write up makes it very understandable

LudeNsoL

iTrader: (14)

Going to be using this reference this weekend on my install. Any other things I should know?

GSbearcat

Hey LudeNsol - just checking to see how your install went? Would love to do the same and these seem to be the best instructions I could find as well. Hope it was successful.

LudeNsoL

iTrader: (14)

Yes it went good. I love my new double din! The only thing I will warn you is that you will lose all bass. So definitely keep in mind you will have to get a sub and amp in the near future.

GSbearcat

Sounds good - thanks for responding

sc4jms

iTrader: (20)

sounds good.

MoneyBagz

Great Write up I just finished this in my gs after searching through the forums for forever trying to find a good write up...I will have to add that the wiring had me a little confused at first so I will add this to help people in the future to match up the wires at the amp...Thanks OP

GREEN----WHITE
FL+ = Pink----FL + = Pink
FL- = Purple----FL- = Orange
FR+ = Light Green---FR+ = Light Green
FR- = Blue----FR- = Purple
RR+ = Red----RR+ = Red
RR- = White---RR- =Green
RL+ = Black----RL+ = Black
RL- = Yellow----RL- = White

Everything under Green goes to the Green harness everything under White is from the white harness

ActNow

The reason I’m posting because I am currently not getting any power to my freshly installed aftermarket radio. I am attempting to run a AVIC 700BT Pioneer. Below is a breakdown of how I have my wires connected. All speakers are wired correctly I tested them using a double A battery, so I will leave those out of my explanation. I have reset my radio, checked my connections that they are secure, and checked the fuse in the back of the radio.

These wires on the left are from the orange stock car harness which I cut/connected to the radio harness wires on the right

1. 12v (ignition) = Grey-------------------------------------------Red (ACC)
2. Constant (Battery) = Blue/yellow------------------Yellow (Battery+) Constant?
3. Illumination – Green-------------------------------Orange/White (Illumination)



This wire on the left was from the large white stock harness, cut/connected to the radio harness on the right.

1. Negative (Ground) = Brown-----------------------------------Black (Ground)

My questions are,
From the stock car harness is a large plug with two gray wires, should I have used one of those instead of the one from the orange?

Is everything in place or am I missing something?

ToddK

Thanks for the write up, it all was very helpful!

dbogotti92

thanks for the writeup it definitely helped me.

LexusK

iTrader: (14)

Hey guys,

I am starting to look into upgrading from the Nakamichi system in my 98 GS400. I have a double din in mind, but am a complete noob when it comes to electronics and wiring. I just wanted to know the following so that the installer doesn't start quoting me extra for things I don't need:
- Do I absolutely need to get new door speakers and a 4-channel amp or can I just keep oem speakers and only upgrade the double din?
- Someone told me to get a double din with a "10band EQ" which will allow me to keep door speakers?
- Does the amp need to be bypassed? How?
- Does it need a harness? What kind?

I also currently have a 12" JL W6 sub powered by a JL 500/1 amp installed. The OEM sub in the deck blew out a long time ago and does not work anymore. Also, one of my rear doors cannot be opened, so I don't think I can even upgrade speakers.

Thank you!

thinking about getting this harness from someone local.

Sceptre

iTrader: (2)

It's been a while and my GS is long gone, but here is my .02 on your questions.

- Do I absolutely need to get new door speakers and a 4-channel amp or can I just keep oem speakers and only upgrade the double din?
As long as the HU (head unit) you choose has power output (95% of the regular off the the shelf HU do it will say something like "40x4" or something) you don't need another amp and speakers. The shop will want you to get new speakers and amp because they will make more money. Granted, it will sound better, but unless you want to win competitions or have a system that is crazy, you won't need it. Now, if your speakers are blown, then you'll want new speakers obviously, and depending on how nice the speakers are, you might need to get another amp that can push more power, and upgrade your speaker cables.
- Someone told me to get a double din with a "10band EQ" which will allow me to keep door speakers?
As long as it has output power you can keep the door speakers. Hopefully your door speakers are still in good shape. See comment above.
- Does the amp need to be bypassed? How?
This thread will show you how. I made it years ago for the sole purpose of bypassing the amp and using stock speakers and wiring.
- Does it need a harness? What kind?
Metra one for Toyota. The first post will have a picture.
I also currently have a 12" JL W6 sub powered by a JL 500/1 amp installed. The OEM sub in the deck blew out a long time ago and does not work anymore. Also, one of my rear doors cannot be opened, so I don't think I can even upgrade speakers.
You can run your current sub set-up off the new headunit. When you install the new HU, hopefully there is a RCA output for subwoofers (it should be labled). I suspect that your current set-up uses the signal from the OEM headunit to subwoofer. You won't be using that, but instead run new RCA cable from the HU subwoofer ouput to the input of the amp. Real simple. Also at the same time run the "remote" (blue wire or blue /white) to the amp so it knows when turn on and off.

Don't get that harness. It's useless, you'll be cutting off most of it. Just get a new one. They are like 5 bucks.

Good luck.

LexusK

iTrader: (14)

Hey Sceptre,

Thanks for the quick response!

In regards to your comment about getting the Metra Harness for $5, is this the one?
It seems like its got the same plugs as the harness I was looking at picking up from someone local. I'm only considering it because the guy totaled his GS before getting the chance to install his double din. He's selling me his faceplate, brackets, harness, a custom heatshield, and that harness in the picture I attached, all for $25. He even said he made it specifically for his GS that had Nakamichi. Basically I think he's already done all the work for me? What do you think? Is that supposed to run all the way to the trunk?