brake light switch issue. - Printable Version

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+--- Thread: brake light switch issue. (/thread-brake-light-switch-issue)

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brake light switch issue. - flstf09 - 04-02-2017

After changing boosters I put the brake light switch back on the pedal.No brake lights.Went and got a new switch,still didn't work it .Finally got it to work ,came back an hour later no brake lights again.Has power coming in but power out when pedal is pressed is very sporadic .What can be  causing this?

RE: brake light switch issue. - midlife - 04-02-2017

A nearly broken wire, perhaps? Check the solid green wire for the output; the green/red wire is the input side to the brake switch.

RE: brake light switch issue. - jpaz - 04-02-2017

I had to replace mine and had no issues. Sorry can't really help, but it sounds like what midlie said or just a bad ground.
My switch worked, but the black button on the spring was worn enough so that it took a pretty firm pedal or foot pressure to make it work. Sitting at a stoplight or checking it in my driveway, they always came on.
I had been wondering why people would run up on me & stop so close to my ass when I would slow down. Well it was cause the lights came on so late.
I thought a few times my brake lights weren't working at all, but they ALYWAYS worked! Drove me nuts that there were that many idiot drivers. Turns out it was me, I guess kinda.
When you buy a car that is supposed to be "totally" restored make sure that the little stuff hasn't been overlooked.

RE: brake light switch issue. - Don C - 04-02-2017

Are the bushing and the two spacer/washers installed correctly, so the switch moves slightly back and forth on the brake pedal pin?

RE: brake light switch issue. - flstf09 - 04-02-2017

I don't believe it's a wiring issue.I have my test light directly on the spade of the output.When it will sporadically light when pedal is pressed it will light brake lights.

RE: brake light switch issue. - flstf09 - 04-02-2017

Yes they spacers and bushing are installed correctly.It doesn't seem to me like it moves enough to make the switch break contact though.

RE: brake light switch issue. - midlife - 04-02-2017

When was the last time the turn signal switch was turned on? Brake light switch output goes to the turn signal switch where it combines with each turn signal for the back lights.

RE: brake light switch issue. - flstf09 - 04-02-2017

A couple weeks ago would be the last time the turn signals were used.Turn signals are working fine.Everything worked fine before I changed booster.

RE: brake light switch issue. - midlife - 04-02-2017

That's not what I intended to ask...when was the last time you installed a brand new turn signal switch? Maybe it went bad on you coincidentally when you changed the booster?

I'll agree with others that a booster change typically includes the push rod, which affects the brake switch itself. If when you push on the brake pedal the power from the brake light is transmitted to the turn signal switch, then the turn signal switch is indicated. If no power is transmitted, the brake switch is suspect. You'll need to pull the turn signal switch connector to make this test.

RE: brake light switch issue. - 69 Rustang - 04-06-2017

I have had trouble with aftermarket brake light switches. They are not as sensitive as an OE switch. A few years ago I went through a few Autozone switches before giving up and getting one from Ford. Installed OE, problem gone.