Six brake light/turn signal mod for 96-04 Mustangs

joekd

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If you are like me you are annoyed that the inside taillight bulb does not work as a brake or turn signal. One option is to get sequential taillights, I couldn't justify spending the money on these but still wanted the safety and good looks of all six bulbs being lit.

You can do this a number of different ways including adding a wire to the existing connector, I went the easy way and used a harness from a junkyard that had a pair of 3157 style connectors already on it

I also used soderless connectors to make it easy to do this while the harness is still attached to the car
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Parts needed:
2 - 3157 bulbs (if your car does not already have these installed, since I would be pulling the lights out I took the opportunity to replace all my bulbs so I bought 6 bulbs total)

2 - 3157 style bulb holders (new these are about $10 each, since they do not need to be Ford connectors I got a set out of a yard for free)

Approx. 2 feet of wire, I used 10 GA for mine

6 - Solderless butt connectors
buttconnectors.jpg


2 - Wire tap connectors
wiretap.jpg


Electrical tape
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Tools needed:

7/16" deep socket and ratchet

Wire cutters

Wire crimpers
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Start by pulling the taillights off your car, the nuts holding them on can be accessed by puling back your trunk carpet, on my 1996 they were held on by four 7/16" bolts.

Once the taillights are off the car you will see the existing wires and bulb holders

brakebulbs.jpg


You will notice that the outer bulb holders have three wires while the inner only have two (no connection to "Major")

Since I am using new bulb holders I cut off the entire inner connector then using the butt connectors connected the existing Ground and Minor connection wires to the new holders (the holders are clearly marked) If you are not using new bulb holders you will have to connect the wire to your existing holder by pulling out the rubber plug to expose the connectors, run a new connection to the Major, cut a slot in the plug and replace

Next I connected a new wire from the "Major" to the existing turn signal wire using a butt connector on the bulb holder end and a wire tap on the existing wires. On the Right side of the car, the signal wire is orange with a blue stripe. On the Left side of the car, the signal wire is green with an orange stripe. (There are two signal wires in the harness. You can make the connection to either one.)

Next step was to put in the new 3157 bulbs and try them out, you can either have a helper step on the brakes or if working alone like I was just turn on the hazard lights, you will now see all 6 bulbs light up.

Use the electrical tape to wrap all your connectors and the new wire to keep them safe. Replace bulbs in the sockets and replace tails on the car.

Congrats on finishing your six light conversion!

Before:
oldtail78.jpg


oldtail81.jpg


After:
newtail87.jpg


newtail85.jpg
 
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