Here is the stereo radio wiring information for your 2011 Audi B8 A4 with the standard, symphony, or Bose systems. It will be useful when installing an aftermarket radio, sound stereo system, or other automotive accessories. Make sure to grab the appropriate tools to test all the wires in your A4. Please check it over and use it as a GUIDE to help you locate the appropriate wires. This schematic is provided free of charge and may not be 100% accurate. Failure to properly test all the wires may lead to vehicle or bodily damage. All information is provided as-is and accuracy is not guaranteed.

If you find any conflicting info please leave a comment with what you found in your Audi B8 A4. If you don’t see the wiring diagram you need comment and we will try to add it ASAP. Thanks for looking!

Keep in mind if you are installing a new radio you may need the radio removal  keys, the wiring harness, the antenna adapter, and the mounting kit as well. See the links below to purchase these items.

2011 Audi A4 Car Audio Stereo Radio Wiring Diagram Schematic Colors

Car Radio Constant 12v+ Wire: Red/Green or Red/Yellow
Car Stereo Ground Wire: Brown
Car Radio Ignition Switched Wire: Not available Grab @ Fusebox

Car Stereo Dimmer Wire:  CAN NETWORK

Car Radio Illumination Wire: Gray/Blue @ Cigarette Lighter
Car Stereo Power Antenna: CAN NETWORK
Car Radio Amp Turn On Wire:  CAN NETWORK

Left Front Speaker Wire (+) Positive: Red/Blue
Left Front Speaker Wire (-) Negative: Brown/Blue
Right Front Speaker Wire (+) Positive: Red/Yellow
Right Front Speaker Wire (-) Negative: Brown/Yellow

Left Rear Speaker Wire (+) Positive: Red/Purple
Left Rear Speaker Wire (-) Negative: Brown/Purple
Right Rear Speaker Wire (+) Positive: White/Green
Right Rear Speaker Wire (-) Negative: Blue/Green

Center Channel Speaker Wire Positive / Negative: Blue/White & Black/White

Subwoofer Speaker Wire Positive / Negative: White/Yellow & Brown/Yellow

Front Speaker Size: N/A

Rear Speaker Size: N/A

Amp Amplifier Location: Driver side of trunk behind carpet
Radio Removal: See service manual