Collective

I have a 93 LS400 with the stock premium pioneer head unit. The aftermarket Nak CD changer failed and I want BT so I am changing it out.

I am installing a Pioneer FHP800BT.

I do a lot of DIY but I don't know a ton about car audio. I need to understand what I am looking at a little better.

Four questions:

1.

I have three harness pieces going into the back of the old head unit. There are two white ones in the middle which appear to be matches for the Scosche TA02 harness i will use unless someone says not to. Then, I have a third one, that is blue and inserted in the bottom middle of the OEM head unit.

What is this, and why is my harness choice apparently leaving it out? Is this for the sub? (Not sure I have one, really).

2.

My new Pioneer head unit has RCA outs for the amp. I have looked for an amp, and I don't see one. Am I just missing it? I bought a Metra Toyota amp integration harness, but there isn't a harness male end that matches it. How do I understand this?

3. My new head unit has only one harness coming out of it for splicing. My old one (and the new Schosche harness) has 2. Am I going to be splicing all the wires from the 2 into the 1?

4. My old head unit has 2 inputs that appear to look like antenna jacks. One is the ordinary size; the other is smaller. I have males to match them in my OEM harness. What is this smaller one?

5. If I don't have an amp, am I going to be unhappy with the HU output? I need something that will push the speakers at ordinary levels, I am not trying to blast anyone out. But I don't want to be underpowered either.

Any help is very much appreciated.

Collective

basketthis

It's actually 5 questions. LOL. It's okay, we all make mistakes.
It is more than likely the input from the factory cd changer located in the trunk. You are seeing the wiring harness for the cd changer to play on the factory radio. You can omit it with no problems.

You have an amp integration harness so you won't need an additional amp. The amp is already in your vehicle. You just plug the RCA's from the Sscosche harness into the RCA outputs on the pioneer HU.
You only need to wire 12v (yellow), ACC (red), and ground (black). The rest you will follow the instructions above and just plug the RCA jacks into the Pioneer headunit. The amp integration should have RCA wires already on it so that you can plug it into an aftermarket HU.
Only use the larger one. This is a Toyota thing for improved reception on the factory radio. You will not need the smaller one when using a Pioneer unit.
No. It will be perfectly fine. It will sound comparable to your factory unit. Maybe even louder. GL

basketthis

EDIT: You may have to hook up the power antenna and amp turn-on wires which will be blue and blue/white usually. Just hook up both to the blue wire coming from the Pioneer unit. It will work GREAT!! GL again. Let us know how things go. And, btw, WELCOME!

Collective

I have obtained 2 aftermarket harnesses. Harness 1 is a Schoshe TA02 harness which has two female junctions that match 2 OEM male harnesses in the car.

I assume I just take each of these, splice these as you have described with the wires in the new Pioneer HU, and then attach them to the matching spots in the in-car harness.

But this is not the amp integration harness that has the RCAs. That is a separate one: a Metra 70-8112 (If I remember correctly). I bought it as a mistake, thinking that I needed it to integrate the amp somehow.

But now that i have it, the plastic junction in it doesn't fit anything in my OEM in car harness.

So this is my next question: if I hook up the first Scosche harness, and I don't have any RCAs hooking into my new HU, am I OK? Am I losing any power, etc.

Thanks for any input--

Andrew Court Collective

basketthis

To answer different parts of that very long question:
You won't be losing any power. The biggest problem you may run into is no sound coming from the speakers. If you do in fact have a factory amp and don't use the amplifier integration harness for that vehicle you may not have sound. In that case, just get the proper harness and plug in the RCAs.
If you don't have a factory amp (which is uncommon in Lexus') you will just use the regular harness.
You can still use the regular speaker outputs to wire into the factory amp. This will just cause the level output to be louder. You're supposed to have a low level input into the factory amp and it will amplify accordingly. If you feed it a high level it will amplify the already high level producing a much "louder" sound at a low volume. So, I guess you could say that there is less control.


I just looked up your harness and see that your factory HU may be one of two. You could have an internally amplified HU or a factory amp located somewhere in the vehicle. If you have the two separate harnesses that match up with your factory harnesses, go ahead and wire those up. See what happens.
If the 8112 doesn't match up, it's definitely the 1761 (metra) two harness plug. Just wire everything straight up and you should be fine. Color to color. Let us know how things go. GL

Collective

Thanks so much. I will try this and let you know.

Andrew Court Collective

pwrdbyrice

ok haha after reading this...im actually a little confused too -_-
i just started working on my car (94LS) and i ordered an aftermarket HU 2 days ago and its going to come with the metra 70-8112 wiring harness...for this harness do i need to keep the factory amp?...or do i need the scosche harness if i dont want the factory amp? thanks

Collective

Put the new HU in as suggested and it looks and works great. BT is great.

Thanks to Basketit.

To address the previous post, it will just depend on the HU. There were 2 different stock HUs (at least) one had the amp in the HU (mine) and would not work with the harness you bought. I made the same mistake and ended up having to get a Scosche TA02 harness, which will work if you have the same stock HU as I did.

IF you have the factor amp under the passenger seat or in the trunk, you may need the harness you bought. I can't be sure though, as I don't have it.

Good luck --

Andrew Court Collective

basketthis

8112 - factory amp integration. it will either fit or it won't.
other - basic toyota harness. just like collective explained it'll either fit or it won't.

I know that if you do have a factory amp under your seat it can cause feedback sound when you have your volume all the way down. (You can hear the engine revvs.) It's almost like a whining. So, I suggest if you do have a factory amp and your are putting in an aftermarket unit, bypass the factory amp. This is something completely different from the harnesses and should only be done by a professional as you can cause damage to your car or to the new radio.


Great job Collective

Glad to see it worked out for you!!! Bet that radio is great! I've done a few and they are pretty cool...