Replacing stock amp

[E.Murray]

I'm re-doing the stereo on my '03 and thought I'd share a few things. There's an oddity about my setup that caused me some headaches, so I'll put the findings out there in case somebody else ends up in the same boat. My car came with a no-name Asian headunit that fits like OEM and has modern functions like Bluetooth, back up cam inputs, nav, etc. Which is fine. The problem was that the harness with the RCA outputs wasn't there. It takes a specific harness and the company didn't respond to requests to buy a new one. So to put an aftermarket amp, I'm stuck with the high level ("speaker level") outputs. Which is also fine. I could either use an amp with high level inputs or use a line out converter.
The problem was that nowhere could I find a wiring diagram for the input side of the stock amp, so I didn't know which wires were for each channel. Since I took the time to sort through them, I figured I'd post so the information would be out there. For the input into the amp (the harness closest to the center of the car), the wires are:

Left Front - Green and Brown/Red
Right Front - Purple and Blue/Red
Left Rear - Brown/Yellow and Brown/Blue
Right Rear - Blue/Red and Blue/White

For the output side (this information can be found other places, but I'll repeat here to save you hunting):

Left Front Woofer - Green/Purple and Green/Lt Green
Left Front Tweeter - Yellow/Black and Yellow/Red
Right Front Woofer - Blue/Green and Blue
Right Front Tweeter - Red/Black and Red
Left Rear - White/Green and White/Purple
Right Rear - Brown/Red and Brown/Green
Center "sub" - White/Orange and White/Blue

It would be nice if the wires were longer, since I'm having to solder an extension on every one of them... But I think it will all fit/work. I'll post when I'm done if anything interesting comes up. Here is the layout for fitting up under the passenger's seat. IMG_1002.jpg

[Zubik]

Should have asked. I looked up the pinouts in FSM. Good luck ��

[Steve M]

You'll probably be okay on space, but it is definitely tight under there. As a reference, this is about as big as you can go without cutting the studs the factory amp mounts to:



That's 9.25"W x 8.75"D x 2.125"H.

FWIW, the previous owner of my car is who started down the aftermarket stereo path on my car. From what I could tell, it looked like the shop he had do the work cut into the factory harness input wires, and just crimped on RCA plug ends. Wasn't quite my style, but I guess it worked for what he wanted. It still retained the factory head unit, but bypassed the amp except for the tiny rear fill speakers. It lasted about a month before I ripped it all out and started from scratch.