I have a pre fab wiring harness on my trailer with 6 wires: Violet/white strip, Violet/orange stripe, Yellow/green stripe, Green, Black/white stripe, Gray/orange stripe. I only need to run a flat plug (4) wire from auto: Green, Yellow, Brown, White. Whitch of the 6 do I connect?

Question edited for clarity, and funky comma use and spaces.
Question moved to model category.

These are the three top websites. According to Just Answer it came with AM/FM Radio, AM/FM Radio Cassette, and two types of AM/FM Cassette / CD Changer. All 4 are shown in the link

https://www.justanswer.com/ford/0hkix-find-1999-ford-taurus-stereo-wiring-harness-diagram.html

These are the other two websites.

1999 Ford Taurus Car Stereo Wire Colors and Locations

The12Volt https://www.the12volt.com > installbay > stereodetail
1999 Ford Taurus Stereo Wiring ; Ground, Black/Light Green ; Illumination, Light Blue/Red ; Dimmer, n/a ; Antenna, Left Rear ; Front Speakers, 5" x 7" Doors.

1999 Ford Taurus Radio Wiring Diagram

MODIFIEDLIFE https://www.modifiedlife.com > 1999-ford-taurus-radi...
Our 1999 Ford Taurus radio wiring diagram shows you all the radio wire colors and what they do. Table of Contents. 1999 Ford Taurus Radio Wiring Diagram; 1999 ...

.. Here is the AM/FM Radio wiring

Factory side wires:
Orange is constant 12 volts
yellow is switched 12 volts
Black Ground
Gray Illumination
Brown Dimmer
Tan LF +
Gray LF-
Lt Grn RF+
Drk Grn RF-
Brown LR+
Yellow LR-
Lt Blue RR+
Drk Blue RR-
The aftermarket reverse harness should be mrked I hope that helps

You can buy an adapter from the larger connector to the smaller one and all will be alright. Most parts houses have the adapter. Also you might find it at a super walmart

Radio 12v  orange  +  radio harness Radio Ground  black  -  radio harness Radio Ignition  dk. green  +  radio harness Radio Illumination  brown  +  radio harness Factory Amp Turn-on  orange  +  radio harness Notes: The amplifier is behind the glove box. Power Antenna  N/A     LF Speaker +/-  tan - gray  +,-  radio harness RF Speaker +/-  lt. green - dk. green  +,-  radio harness LR Speaker +/-  brown - yellow  +,-  radio harness RR Speaker +/-  dk. blue - lt. blue  +,-  radio harness

hot at all times: white/violet + light green/violet
hot in acc or run: black/pink
grounds: black/light green + black
instrument illumination: light blue/red
GEM module: gray/black
LF speaker: orange/light green + light blue/white
RF speaker: white/light blue + dark green/orange
LR speaker: tan/yellow + gray/light blue
RR speaker: orange/red + brown/pink
cellular/telephone: tan
this is for premium sound radio.

Battery GREEN/BLACK (+) RADIO HARNESS
Accesory BLACK/PINK (+) RADIO HARNESS
Ground BLACK/GREEN (-) RADIO HARNESS
LF Speaker (+) ORANGE/GREEN
LF Speaker (-) BLUE/WHITE
RF Speaker (+) TAN/GREEN
RF Speaker (-) GREEN/ORANGE
LR Speaker (+) GRAY/BLUE
LR Speaker (-) BROWN/YELLOW
RR Speaker (+) BLACK/VIOLET
RR Speaker (-) ORANGE/VIOLET

Factory in-dash wire harness that
snaps into the factory radio.
AS VIEWED FROM MATING END OF CONNECTOR
E F G H I N O P
A B C D J K L M
Note: using an optional snap on wire harness adapter will simplify the wiring. Most snap on
wire harness adapters have already converted and color coded the wires from the auto
makers in dash wire harness to match typical aftermarket radio wire colors.
** The wire colors listed in the chart above are typical for these vehicles during these years
but may not be the exact colors for this vehicle. This is another reason to use a snap on
wire harness adapter. **
Typical Honda/Acura "Typical" New Radio
Pin What It Is In Dash Wire Color Equivalent Wire Color
A Right Rear Spkr (+) Red w/ Yellow Stripe Purple
B Left Rear Spkr (+) Blue w/ Yellow Stripe Green
C Power Antenna Trigger Brown w/ White Stripe Blue or Blue w/ Wht Stripe
D +12 Volt Ignition Wire Yellow w/ Red Stripe Red
E Right Rear Spkr (-) Brown w/ White Stripe Purple w/ Black Stripe
F Left Rear Spkr (-) Gray w/ White Stripe Green w/ Black Stripe
G Ground Wire Black Black
H Do Not Use
I Do Not Use
J +12 Volt Battery Wire White w/ Yellow or Blu Stripe Yellow
K Dash Light Dimmer Wire Orange
L Left Front Spkr (+) Blue w/ Green Stripe White
M Right Front Spkr (+) Red w/ Green Stripe Gray
N Do Not Use
O Left Front Spkr (-) Gray w/ Black Stripe White w/ Black Stripe
P Right Front Spkr (-) Brown w/ Black Stripe Gray w/ Black Stripe

Pin --- Color --- Stripe --- Function

Harness 1

1 --- White --- Black --- Left front +
2 --- Gray --- Black --- Left front -
3 --- White --- Purple --- Left rear +
4 --- Gray --- White --- Left rear -
5 --- White --- Red --- Right front +
6 --- Gray --- Red --- Right front -
7 --- White --- (none) --- Right rear +
8 --- Gray --- (none) --- Right rear -

Harness 2

1 --- (not used)
2 --- Black --- Green --- Radio Ground
3 --- (not used)
4 --- Orange (thin) --- Black --- Radio Illumination
5 --- Green --- Yellow --- Radio switch
6 --- Black --- Yellow --- Radio Ground
7 --- Orange (thick) --- Black --- Radio 12V

Harness 3

1 --- White --- Green --- Speed sensor
2 --- (not used)
3 --- (not used)
4 --- (not used)
5 --- (not used)
6 --- (not used)

Battery GREEN/BLACK (+) RADIO HARNESS
Accesory BLACK/PINK (+) RADIO HARNESS
Ground BLACK/GREEN (-) RADIO HARNESS
LF Speaker (+) ORANGE/GREEN
LF Speaker (-) BLUE/WHITE
RF Speaker (+) TAN/GREEN
RF Speaker (-) GREEN/ORANGE
LR Speaker (+) GRAY/BLUE
LR Speaker (-) BROWN/YELLOW
RR Speaker (+) BLACK/VIOLET
RR Speaker (-) ORANGE/VIOLET