View Full Version : '08 xB wiring harness?

06-08-2007, 12:45 PM
I need to install some hi-level (speaker) inputs to my Bazooka Tube. I plan on running the wires from the head unit down driver-side of my car. I already ran the power from the battery down the passenger side.

I have a few questions though (I've never installed an amp before).

1) Should I tap the rear speaker lines or cut them (and disable the rear speakers)?
2) What colors are what on the OEM harness?

I had planned on running my aftermarket speakwire from the back door to the tube but I can't get through the hinge on the door. It's a special plug and not a hole so I can't get through and I'm not willing to drill anything.

I'd really appreciate advice.

06-08-2007, 05:55 PM
If you take out your HU, it has a label on the topside with a color diagram explaining the wires... and I would not cut any wire in a new car, simply splicing into it is fine.

As far as running wires thru doors, I like to use the heavy duty zip ties from Home Depot.

06-08-2007, 06:12 PM
Is it ok to have the speaker still driven by the HU as well as the amp? Will that just leave the speaker underpowered?

06-09-2007, 03:55 PM
Ok from what i understand! ur using a line out conveter on ur factory radio!

So ur can get RCA input to ur amplifier.

2 things u can do.

1. U can (Tag) take a small T-tap with a insullated male conector/splice. to ur rear speakers wires then run ur rca from that pannel to ur amp. But u need to be sure whats postive and negative that way. No this will not underpower ur speaker ur just pulling signal not pulling power with resistance or OHMS.

2. U can go Buy a Metra # 70-1761 aftermarket radio plug take ur dash apart pull ur radio plug that harness in. And Tag Those wires with the same colors that match with ur line out converter. Not the Aftermarket plug wires but on the otherside the harness that coinside with the radio. So the wires that plug into ur factory radio. then drop ur remote wire and RCA from the dash.

U use the same process for the remote wire just use the red wire (acc).

06-09-2007, 06:06 PM
I'm just going to tap the + and - lines for both rear speakers. I'll tap them behind the head unit. I'll then run my new speaker wire down the side of car to the speaker-level inputs on my new amp. I just bought and amp and not a bazooka tube. I'm going to use it with an unpowered tube I have laying around.

The amp I bought matches my interior nicely. I'll post some pictures when I'm done.

06-09-2007, 06:40 PM
So why would u want to run high level input and run 4 speaker wires down instead of running low level input and run rca input. with one wire? U get a much beter signal running RCA

Plus u must not uderstand what i was telling u to do with that adapter. Ok pull ur radio out and find the speaker wires & acc power. A way to do that is to get a aftermarket plug and use those colors to tell u what the colors of the wires u need to hook up from your factory plug. and Tag + and - that way.

Also ur killing ur signal running high level input into that amp. Yes it will work and yes sometimes it sounds good but signaling is eveything. Remeber ur chain is as strong as ur weakest link.

Since u want to keep ur Factory unit in ur Dash Look into the (JL clean sweep) and Alpine(PXE-H650) these are signal proccesers to help ur inputs into ur amp.

06-09-2007, 06:51 PM
There's no wiring harness available for the 08 scion xB yet. So I'm on my own to figure out what wire is what. Since there are no RCAs on the back of the HU I'm using hi-level all the way. It's only 200 watts peak and since the power is down the other side of the car the noise should be small.

All the speaker and power wires have been run which was easy.

06-11-2007, 07:01 PM
Sorry I haven't responded faster but i don't know who told u there is not a harness out for the 08 XB but they are wrong!!! Metra 70-1761 is the harness for that car!!! 100% sure.