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no brake lights

34K views 46 replies 17 participants last post by  Bad69cat 
#1 ·
Hi everyone Im experiencing problems with my brake lights on my 67. They dont come on when applying the brake. My tailights come.on when u turns the headlights on, and my sequentials work as work as well. I located a small fuse box on firewall but all I can see are fuses for cigarette lighter and dome lights. Your guys help is most appreciated
 
#31 ·
:jump3: You won the battle!
 
#33 ·
I had this problem in my 67 and it was the brake light switch. They had worked when I bought the car and then just stopped one day. There is nothing worse than trying to replace this switch on a Cougar with a clutch pedal. I had the seat out of the car laying on my back under the dash with my feet up on the back seat and there was no way to get my hand between the clutch, steering column, and brake to get at this damn thing. I got it eventually but really never want to again.
 
#37 ·
Yeah, seen that pic too. That's for power brakes, but still shows a bushing. I have manual brakes, straight push rod, and bushing. The rod and switch seem to move together and the switch is never activated. It doesn't work with or without a rod bushing.

I finished rebuilding the dash harness & column. Everything works. Brake lights work jumpered out, and with the switch unmounted and activated with my thumbs.

Hummm..........
 
#38 ·
The configuration is for Manual OR Power, the bushing action does not change. The switches may be different, but your manual could use either.


http://www2.cougarpartscatalog.com/c9zz-13480-a.html

The bushing must be larger diameter than the pedal arm pin so that the pedal moves forward within in to bring the switch into contact with the pushrod.

So either the bushing is too small, or the assembly is too tight.
 
#39 ·
The power brake switch, if used with manual brakes, is too sensitive. It will hang on when you least expect it and either melt the wiring or run your battery flat.

The manual brake switch, if used with power brakes, will never work.

Either way you need the bushing.
 
#40 ·
By the way that drawing is terrible, it does not show what actually happens to make the switch actuate.

The switch is fixed against the flat on the brake push rod. When you press the pedal the angle of the switch is changed in relation to the pushrod. The flat part of the pushrod is no longer parallel with the body of the switch.
 
#41 · (Edited)
The switch is fixed against the flat on the brake push rod. When you press the pedal the angle of the switch is changed in relation to the pushrod. The flat part of the pushrod is no longer parallel with the body of the switch.
That's how I perceived it to work. As it rotates, either the top or bottom of the flat rod end actuates the switch. Unfortunately, my switch and rod move in tandem, never triggering the switch. My stock switch (the one in the car when I bought it 20yrs ago) still works. I bought a new switch and it acts the same way.

The bushing must be larger diameter than the pedal arm pin so that the pedal moves forward within in to bring the switch into contact with the pushrod.

So either the bushing is too small, or the assembly is too tight.
My bushing is an exact fit between the pedal pin and the rod. So I need a thinner bushing to allow a little bit of play between the bushing and the pedal pin?

(BTW, the switch freely rotates on the pedal pin. there's no stay/stop that holds it in place. Is this correct?)
 
#43 ·
Here is a good pic of the Mustang, the Cougar is more crowded under there. Looks like I forgot to push the retaining clip all the way in last weekend when I mounted up the switch.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/43720300@N08/25669938413/in/dateposted-public/" title="IMG_2225"><img src="https://farm2.staticflickr.com/1593/25669938413_57dc7ca216_c.jpg" width="800" height="600" alt="IMG_2225"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>
 
#44 ·
Are those power brakes? I have 3"-4" of rod showing between the switch and the rubber boot. Ill order the spacer from WCCC and hope that fixes the problem cuz I thats all I got left to try! I wonder if my 68 has the wrong master cylinder/rod assembly in it..........
 
#45 ·
Well.......got the new bushing in. Still didn't fix the problem. Ill switch out the old switch for the new switch later today and see what I get. If that doesn't work, I may have to install a generic switch up top seeing there's a bracket there for it?!
 
#46 ·
Woo Hoo! My brake lights work! The new bushing didn't help with the new switch or the old switch. Turned the switches right side up and upside down. Nada! Ended up removing the bushing altogether and they worked! Both switches work without the bushing. (Previous attempts to fix brake lights were before new turn signal switch replacement :( ) Everything I've seen shows a bushing in the rod end. This leads me to think that the PO may have installed an incorrect push rod! I will be exploring this shortly.
 
#47 ·
Good news! - But you will need something to keep things more solid and dependable. At least you have it narrowed down - should be easy to deal with now......
 
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