Let's build a complete head unit wires color code

[hugobr]

Hello Guys,

I recently bought a 2012 Chevy Sonic LT Hatch here in Brazil, and I want to swap the headunit for an aftermarket android one.

My goal is to retain as much as possible of the factory funcionalities, like, usb ports and audio jack, Steering wheel control, etc... I don't have any problems whatsoever cutting wires and soldering them, but I am having a hard time finding the meaning of the Sonic color coding.


From another thread in this forum I already found color coding for speakers:

Front Left- Blue & Blue/Brown
Front Right- Yellow & Yellow/Black
Rear Left- Green & Green/Black
Rear Right- White & Blue/Black
Power Socket Positive- Purple/Yellow

But I still need to know:

ACC (Turn on ignition):
Dimming(?):
Reverse gear wire:


USB port and audio Jack
USB:
+5v:
Tx:
Rx:
GND:

Audio Jack:
Right:
Left:
Gnd:


Steering Wheel control
Does this system uses one wire or three?
What colors?


Chimes
I have no Idea why manufacters connects this to the headunit, for me it should be a completely separated system.

What I know so far: there must be 4 sensors that activate this, door open, key in the ignition, headlamp and seatbelts.

Whats the headunit`s purpose in all this? and what wires?




Any information will be appreciated

Regards

 

[Vicarious]

I know it's a pain in the butt, but the easy way to check which one the ACC, Dimmer and Reverse wires are is with a voltmeter.

Turn the car to ACC and check any wires you don't know know yet. The ACC wire will be one of two wires with 12V.
Now, adjust the dimmer and recheck those two wires. One will have gone down in voltage while the other is still at 12V. The 12V one is ACC. The one that adjusted is the dimmer. Reverse can be easily found by simply checking to see which wire goes from nothing to being at voltage when in reverse.

Anyways, I found some wiring diagrams online, though I can't speak to the accuracy of them:

 

[TurtleOverlord]

These are from the 2013 service manual

Sent from my iPhone using Tapatalk

 

[skurtov]

Metra already makes kits to retain everything....

 

[hugobr]

@Vicarious,

Thanks a lot for the input, your pdf already helps a lot, yours and @TurtleOverlords!

I'll test this schematic and will come back with the results


@skurtov, Yeah I know, but in brazil we don`t have them, also, some people might want to save that money and do it themselves, so its a good idea to archive this info!