Every Mustang Owner needs to see this for Brake Light Safety

[PNewitt]

This is something that I think every Mustang owner needs to get a good look at.

It's a photo of the backside of the brake light switch pigtail/connector, that is located just above your brake pedal, from the under-dash wiring harness.

The brake light switch plugs into this (on the other side), and the side you are looking at is the back side.

This one is from my GT/CS, and I've since replaced it. Long ago, I tried to solder it, with mixed results. What I want to point out is how the wires come together, and how they fray apart. Years of movement from the brake pedal--thousands of times--wears doen the wires, and they will fray like this, leaving only a few strands to run all that power to the (six bulbs!) of the taillights. This is a big potential problem, and one that you need to get a good look at on your car. The frayed strands can touch each other at this location, and cause shorting, and grounding. This is one way why your brake lights can be so dim.

(as another side note--be sure to use those plastic (nylon) washers when replacing the brake light switch onto the brake pedal bracket. Without them, you lose about 1/2 second to getting the brake lights to come on.)

I haven't seen these "brake light switch connectors" as replacement parts ever, and I think that the companies that make wiring for older Fords should make them as a separate item that can be spliced into the under-dash harness.

In the meantime, you might want to look for a replacement connector from a junkyard, and replace your old one. Give yourself about 6 or more inches of wire to work with. Be absolutely sure to get the polarity right when rewiring a new connector, and (I would) solder the wires together, and use heat shrink tubing, to assure a strong, positive connection. If you're unsure, or not versed in auto electrical work, take it to a professional.

Paul N.

 

[case12]

I agree. I had this problem with my CS. It took a while to trace down. I finally found it and did some re-soldering, and got it back together and working. Casey

 

[rvrtrash]

Paul, I have a question and possible new info for you. To refresh memories, my CS was only on the road 10 years and I believe the 52K on the odometer is original. I recently replaced my brake switch and discovered a short wiring harness that goes between the connector from the main harness and the brake switch. The wires are about 3" long with factory Ford connectors on both ends. I removed the short harness to experiment and the main harness plugs right on to the brake switch. It appears this 3" long harness does nothing except extend the harness a little and maybe provide a replaceable piece for the situation you're describing. Have you ever heard of this before. I know when I saw it, I thought it was odd, but put it back in, just because it was there originally.
Steve

PS, If you want a picture, I can go out to the shop in the morning a get it for you.
S.

 

[PFSlim]

Everyone

Good information. I did not look at this connector at all when installing my wiring harness. My bet is that mine could be attended to some. Once again, this site is an excellent source of information to keep our mustang's on the road.

Paul

 

[ViCatz]

I believe the brake wires were too short for a period of time that extended into early 69 production.

 

[Perkchiro]

Interesting threat: Thanks for bringing this to our attention Paul. When I restored my car and pulled the wiring harness, my brake switch plug was gone. Somewhere in it's life, someone cut the wires and attached them to the switch with female blade connectors. Since there were no reproductions available, I soldered and shrink wrapped new wiring with new insulated female blade connectors to the switch. There's not a lot of movement when the brake pedal is depressed. I've checked and double checked this and there seems to be no stress on the wiring with pedal travel. I would love to just replace it with an original or repo plug, so until I locate one, this is the best I can do.

 

[RASCalif]

I have the exact same symptoms you described. Will check this asap. Thanks!

 

[di81977]

Was checking out my under dash wiring and noticed my wires at the brake light switch are hot.

Questions -
Anyone know if there is a replacement part yet?
Is the switch specific to the GT/CS, HCS, Shelby? Someone told me they thought the Cougar switch might be the same.

Thanks

 

[ViCatz]

67s that I have worked on have thin wires to brake lite switch that feeds six taillights.
So if you have to, use heavier gauge brake switch wiring from 69.
Also clean up the wiring at turn signal to main harness connection under dash with electrical contact cleaner. This will help your rear lights and horn to work better.
Cougar and TBird switch sounds about right as they both have six taillights to run thru the switch.
C7W is Cougar.
What does your switch say?
I have a fair box of original brake lite switches but most are C6O Fairlane switches where the tabs are opposite side and the switch is made for two taillights.
Most switches available aftermarket are the 2 taillight kind.