car with multiple 12 constant wire

on cars that have multiple how do you deceide on what wire to use for remote start applications, my 03 taurus has 4 of these wires but the alarm only has 2 outputs. should i use a relay for the other two?

If you are asking about the wires at the Ignition Switch On your Taurus:
Usually those wires terminate together in the loom, Junction Box / Fuse Box or elswhere

You just need to be concerned if the wires in question will carry the added load of your RS....................which they will.
On some Vehicles U have to use a Constant from the Battery because the Switch wires or Fuse Block does not carry sufficient Power

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MO

Don't Learn from Others Mistakes
You Might Be the One That Knows.

Additional note to the above post.

If you are putting in an alarm or starter. The constant wire that you should be concern about is the GREEN/ purle wire at the ignition harness. It's the one that can carry the load when you are putting in an alarm and starter.   Below is the wiring diagram for your vechile.



DIRECTWIRE™ WIRING INFORMATION - FORD / TAURUS / 2003 / Remote Start


12volts lt. GREEN/ purple   +   ignition harness
Starter RED / lt. blue   +   ignition harness
Second Starter N/A       
Ignition RED / lt. green   +   ignition harness
Second Ignition N/A       
Third Ignition N/A       
Accessory gray / YELLOW   +   ignition harness
Second Accessory BLACK/ lt. green   +   ignition harness
Keysense          
Power Lock pink / YELLOW   -   26 pin plug @ GEM
Notes: The GEM (Generic Electronic Module) is to the left of the steering column.
Power Unlock pink/lt. green   -   26 pin plug @ GEM
Notes: The GEM (Generic Electronic Module) is to the left of the steering column.
Lock Motor pink/black   5wi top plug of fuse box
Unlock Motor RED / white   5wi top plug of fuse box
Parking Lights+ brown   +   headlight switch or fusebox
Parking Lights- N/A       
Hazards          
Turn Signal(L)          
Turn Signal(R)          
Reverse Light BLACK/ pink   +     
Door Trigger BLACK/ orange   -   20 pin plug at GEM
Notes: This wire controls the door ajar indicator on the dash, must cut the wire and diode isolate it from the instrument cluster. Can also use individual negative door trigger wires in the 26 pin plug at the GEM. They are: yellow/black (LF), gray/red (RF), lt. GREEN/ YELLOW (LR), and pink/lt. blue (RR).

The GEM (Generic Electronic Module) is to the left of the steering column.
Dome Supervision BLACK/ lt. blue   +   top plug of fuse box
Trunk/Hatch Pin          
Notes: On the sedans use BLACK/ pink (-) at the light in the trunk. On the wagons use WHITE/ purple (-) in the 26 pin plug at the GEM.
Hood Pin tan/lt. green   -   26 pin plug at GEM
Notes: The GEM (Generic Electronic Module) is to the left of the steering column.
Trunk/Hatch Release          
Notes: With keyless entry it is purple / YELLOW (-) at the switch. Without keyless entry it is gray/red (+) at the switch. On the wagon, to unlock just the rear hatch use yellow/lt. green (-) in the 26 pin plug at the GEM.
Power Sliding Door N/A       
Factory Alarm Arm          
Factory Alarm Disarm pink/white   -   26 pin plug at GEM
Notes: The GEM (Generic Electronic Module) is to the left of the steering column.
Disarm No Unlock see factory alarm disarm       
Tachometer tan / YELLOW   ac   PCM
Notes: The PCM (Powertrain Control Module) is on the passenger side firewall under the hood.
Wait to start N/A       
Brake Wire RED / lt. green   +   brake pedal switch
Parking Brake          
Horn Trigger purple or blue   -   steering column
Memory Seat 1          
Memory Seat 2          
Memory Seat 3          
Immobilizer Bypass Module: Required: Yes Type: SecuriLock Part #: 556S, 556U, or 555U
Notes: N/A



      
This wiring information is being provided free of charge on an "as is" basis, without any representation or warranty. It is your responsibility to verify any circuit before interfacing with it using a digital multimeter.
Directed electronics, Inc. assumes no responsibility with regards to the accuracy or currency of this information. Proper installation in every case is and remains the responsibility of the installer. DEI assumes no liability or responsibility resulting from improper installation, even in reliance upon this information.





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