For 2008 Honda Civic, it would be as shown below. For all other years, you may want to try looking for your specific year here
where the information was originally posted.2008 Honda Civic Car Stereo Wiring Guide
Car Radio Battery Constant 12v+ Wire: White
Car Radio Accessory Switched 12v+ Wire: Violet
Car Radio Ground Wire: Black
Car Radio Illumination Wire: Red/Black
Car Stereo Dimmer Wire: Red
Car Stereo Antenna Trigger Wire: Gray
Car Stereo Amp Trigger Wire: Light Blue
Car Stereo Amplifier Location: Located in the front of the center console under the center of the dash.
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Light Green
Left Front Speaker Negative Wire (-): Pink
Right Front Speaker Positive Wire (+): Gray
Right Front Speaker Negative Wire (-): Brown
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Yellow
Left Rear Speaker Negative Wire (-): Brown
Right Rear Speaker Positive Wire (+): Blue
Right Rear Speaker Negative Wire (-): Orange
Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.
Good luck and kind regards.
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