Electrical Brake Light Switch

[Shane8996GTLX]

Thanks. What did you pay for yours.

 

[wmburns]

What I'm not seeing is the results of the test CONFIRMING there is +12 volts on BOTH sides of the brake on/off switch (BOO) with the brake pedal depressed. Use a KNOWN good ground.

What to do next depends upon this test result. Anything else is just guessing.

If interested in getting a copy of the Ford service manual with wiring diagrams I maybe able to help. PM if interested.

 

[Shane8996GTLX]

Only 12 volts noted to red/ green wire. Can't source any to Green/red.

 

[wmburns]

Only 12 volts noted to red/ green wire. Can't source any to Green/red.

Confirm this test was done with the brake pedal depressed.

If the test results are correct, the only reasonable possibility is a problem with the brake on/off switch.

Want further proof of the diagnosis? Short/jump the RD/GN and GR/RD wires together. This should cause the brake lights to come on.

Now as to what the root problem is. This could be:

• Bad brake on/off switch
• incorrectly adjusted or installed brake on/off switch. For example the switch is not activating when the pedal is depressed.
• Wiring fault such that power isn't really passing through the switch.

 

[Shane8996GTLX]

I will try the short idea. Maybe shim the switch? Pedal was in normal state and pressed with the same result.

 

[Shane8996GTLX]

Do you have power at one of those wires?
What year/model are we talking about

There is power to one of the wires. It's. 96 GT

 

[General karthief]

Power in to switch, no power coming out with switch activated, I'd say its the switch, someone mentioned touching the wires together see if lights worked, try that?

 

[Shane8996GTLX]

Can I text you it would make it easier ? I tried the old and new switch as well as touching the wires. No luck.

 

[General karthief]

Then your problem is between there and the back, you need a wire diagram, have you checked the wires in the trunk?
Do you have a volt olm meter

 

[Shane8996GTLX]

I don't know what wires to check and have no wire diagram

 

[Shane8996GTLX]

Yes I have a voltmeter

 

[General karthief]

Did you say you pulled on a wire and thats when the problem started?
What color was it
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-Exterior-Lighting.gif

 

[Shane8996GTLX]

It was a small black wire but I have no idea where it would of gone.

 

[General karthief]

The black wire your talking about, was it in the boo switch area

 

[Shane8996GTLX]

Yes on the pigtail.

 

[General karthief]

Is the 'pig tail' you talk about the plug for the switch?
Does your turn signals work?

 

[Shane8996GTLX]

Yes for the switch. TS work

 

[General karthief]

Does the switch have three spades or two

 

[Shane8996GTLX]

By spades you mean connection there's 2.

 

[General karthief]

Yea, found a pic.
And you have two wires in the connector red and lt green