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Found on:
http://www.modifiedlife.com/2008-for...iring-diagram/
2008 Ford Focus Car Stereo Wiring Diagram
Car Radio Battery Constant 12v+ Wire: White/Red
Car Radio Accessory Switched 12v+ Wire: Gray/Orange & Violet/Orange (This vehicle uses the can data network for accessory turn on.)
Car Radio Ground Wire: Black/Blue
Car Radio Illumination Wire: Gray/Orange & Violet/Orange (This vehicle uses the can data network for illumination and dimmer controls.)
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: Black
Car Stereo Amp Trigger Wire: Violet/Red
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): White
Left Front Speaker Negative Wire (-): White/Brown
Right Front Speaker Positive Wire (+): White/Violet
Right Front Speaker Negative Wire (-): White/Orange
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): White/Green
Left Rear Speaker Negative Wire (-): Brown/Yellow
Right Rear Speaker Positive Wire (+): Brown/White
Right Rear Speaker Negative Wire (-): Brown/Blue