I have a light with instructions to be sure and hook + wire to positive. I have a light green wire and a light brown wire, so which is + wire ?

put the original radio back in. My guess is whoever installed the radio cut something they should not have.

Windstar Car Stereo Radio Wiring Diagram - All years
Car Radio Constant 12v+ Wire: Green/Violet Car Radio Switched 12v+ Wire: Yellow/Black Car Radio Ground Wire: Black/Light Green Car Radio Illumination Wire: Green
Left Front Speaker Positive Wire (+): Orange/Light Green Left Front Speaker Negative Wire (-): Light Blue/White Right Front Speaker Positive Wire (+): White/Light Green Right Front Speaker Negative Wire (-): Dark Green/Orange
Left Rear Speaker Positive Wire (+): Light Brown/White Left Rear Speaker Negative Wire (-): Light Brown/Yellow Right Rear Speaker Positive Wire (+): Light Brown/Green Right Rear Speaker Negative Wire (-): Brown/Pink

Speakers
1995-1998: 5" x 7" Front door and side panel 1999-2003: 6" x 8" Front and rear door

1983 Chevrolet S10 Pickup Truck Car Radio Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Orange
Car Radio Accessory Switched 12v+ Wire: Yellow
Car Radio Ground Wire: Black
Car Radio Illumination Wire: Gray
Car Stereo Dimmer Wire: Brown
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: 4? x 6?
Car Audio Front Speakers Location: Dash
Left Front Speaker Positive Wire (+): Tan
Left Front Speaker Negative Wire (-): Gray
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Dark Green
Car Audio Rear Speakers Size: 4? x 10?
Car Audio Rear Speakers Location: Rear Corners
Left Rear Speaker Positive Wire (+): Brown
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Dark Blue
Right Rear Speaker Negative Wire (-): Light Blue

Check this...

1996 Ford Windstar Car Stereo Radio Wiring Diagram
Car Radio Constant 12v+ Wire: Green/Violet
Car Radio Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Black/Light Green
Car Radio Illumination Wire: Green
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Orange/Light Green
Left Front Speaker Negative Wire (-): Light Blue/White
Right Front Speaker Positive Wire (+): White/Light Green
Right Front Speaker Negative Wire (-): Dark Green/Orange
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Light Brown/White
Left Rear Speaker Negative Wire (-): Light Brown/Yellow
Right Rear Speaker Positive Wire (+): Light Brown/Green
Right Rear Speaker Negative Wire (-): Brown/Pink

Hope helps (remember comment and rated this).

You should really invest in a $15 wire harness so you do not have to cut the factory plug.
Instructions will be in the package - but in the event you dont have a factory plug due to theft - here is the vehicle's wiring color codes...

Car Radio Battery Constant 12v+ Wire: Light Green/Pink
Car Radio Accessory Switched 12v+ Wire: Black/Violet
Car Radio Ground Wire: Black
Car Radio Illumination Wire: Light Blue/Red
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: Blue

Left Front Speaker Positive Wire (+): Light Blue/White
Left Front Speaker Negative Wire (-): Orange/Light Green
Right Front Speaker Positive Wire (+): Dark Green
Right Front Speaker Negative Wire (-): White/Light Green

Left Rear Speaker Positive Wire (+): Tan/Yellow
Left Rear Speaker Negative Wire (-): Gray/Light Blue
Right Rear Speaker Positive Wire (+): Brown/Pink
Right Rear Speaker Negative Wire (-): Orange/Red

Thanks for using FixYa!!

si intiendes ingles un poco, aqui es los colores por los cables para estereo tuya..
Car Radio Constant 12v+ Wire: Green/Violet
Car Radio Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Black/Light Green
Car Radio Illumination Wire: Green
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Orange/Light Green
Left Front Speaker Negative Wire (-): Light Blue/White
Right Front Speaker Positive Wire (+): White/Light Green
Right Front Speaker Negative Wire (-): Dark Green/Orange
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Light Brown/White
Left Rear Speaker Negative Wire (-): Light Brown/Yellow
Right Rear Speaker Positive Wire (+): Light Brown/Green
Right Rear Speaker Negative Wire (-): Brown/Pink

2001 Ford Windstar Car Stereo Radio Wiring Diagram
Car Radio Constant 12v+ Wire: Green/Violet
Car Radio Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Black/Light Green
Car Radio Illumination Wire: Green
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Orange/Light Green
Left Front Speaker Negative Wire (-): Light Blue/White
Right Front Speaker Positive Wire (+): White/Light Green
Right Front Speaker Negative Wire (-): Dark Green/Orange
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Light Brown/White
Left Rear Speaker Negative Wire (-): Light Brown/Yellow
Right Rear Speaker Positive Wire (+): Light Brown/Green
Right Rear Speaker Negative Wire (-): Brown/Pink

Constant 12V+ Brown/White
Switched 12V+ Orange
Ground Black/Light Green
Illumination Pink/Black
Dimmer Pink
Front Speakers 5" x 7" Doors
Left Front (+) Gray/Blue
Left Front (-) Yellow/Blue
Right Front (+) Blue
Right Front (-) Yellow
Rear Speakers 5" x 7" Side Panels

Left Rear (+) Blue/White
Left Rear (-) Blue/White
Right Rear (+) Blue/Black
Right Rear (-) Red/Blue

Thanks for using FixYa - a FixYa rating is appreciated for answering your FREE question.

Car Radio Constant 12v+ Wire: Green/Violet
Car Radio Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Black/Light Green
Car Radio Illumination Wire: Green
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Orange/Light Green
Left Front Speaker Negative Wire (-): Light Blue/White
Right Front Speaker Positive Wire (+): White/Light Green
Right Front Speaker Negative Wire (-): Dark Green/Orange
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Light Brown/White
Left Rear Speaker Negative Wire (-): Light Brown/Yellow
Right Rear Speaker Positive Wire (+): Light Brown/Green
Right Rear Speaker Negative Wire (-): Brown/Pink

1995 Ford Windstar Car Stereo Radio Wiring Diagram
Car Radio Constant 12v+ Wire: Green/Violet
Car Radio Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Black/Light Green
Car Radio Illumination Wire: Green
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Orange/Light Green
Left Front Speaker Negative Wire (-): Light Blue/White
Right Front Speaker Positive Wire (+): White/Light Green
Right Front Speaker Negative Wire (-): Dark Green/Orange
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Light Brown/White
Left Rear Speaker Negative Wire (-): Light Brown/Yellow
Right Rear Speaker Positive Wire (+): Light Brown/Green
Right Rear Speaker Negative Wire (-): Brown/Pink
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