So my brake lights worked and than nothing. I have led taillights on my truck project the blinkers and hazards work fine but the brake lights don't. I checked the connections and everything seems to be plugged in. Can anyone suggest what else to look at
Not very much info on what you have, what model truck, stock wiring harness or aftermarket, did LED brake lights work before?
If the brake lights use the same LEDs as the 4 way flasher it could be the brake light switch, a fuse or the turn signal switch. I'd check for power at the brake light switch first then see if it has power at both sides with the pedal depressed.
If the led's are getting a signal from every other source, i would look at the brake switch and related wiring
What type of brake light switch are you using? One of those pressure-actuated ones? Or a mechanical type?
What year cars used these 2 wire pressuse actuated switches? Are all brakes switches the same as far as pressure to actuate them?
Check for power in and then the power out when you have someone push the pedal just as I told you to do on the truck board. You absolutely have to know that you have power running to the switch and then you have to know that you have power running out of the switch. Once you have that you go up the wire to see where the problem is. Autozone and O'Reilly's sell test lights for under 10 bucks. I ran one of those Ford switches on my 48 for a lot of years and replaced them about every 18 months as they crap out on a regular basis when they are down under the truck for some reason
Sometimes you have to add a relay to make a super ground in the circuit for the LEDs. I don't understand it but it worked on a friends car.???????
check for power/continuity at your connector at the switch then across the switch itself , them connectors are not correct for the pin end s, those have a small contact area and the connectors corrode and break contact with the pins or the wires corrode at the junction . if you want the proper connector mac makes it http://www.macsautoparts.com/ford_thunderbird/ford-thunderbird-brake-light-switch-plug-molded-waterproof-plug-w-2-wire-leads-1955-64.html or this type http://www.macsautoparts.com/ford_thunderbird/ford-thunderbird-brake-light-switch-plugs-1955-66.html and put dielectric grease around the pins to protect them from moisture
The cheap $5:00 pressure switches last a month or two. Replace it with a Motorcraft or Harly-Davidson switch and you will be fine.
I would have jumpered the switch in a New York minute, which would point to the switch or the wiring. A simple touch with a screwdriver would do the trick. Cosmo P.S. I did write a tech piece on a very simple relay that makes the switches last practically forever. only additional wiring is a ground lead to the relay. Perhaps 4 inches of copper...
I had the same problem. The plug from the steering column, (the flat plug with about 6 wires in it) had a little corrosion on it. Your signals and brake lights run thru there. Sometimes it worked and sometimes not? Check it for good contact. Good luck!
Brake switch should have its own fuse, If that's good and you have power to switch. but not out switch is bad, from there it goes to turn signal switch.
Maybe the info. on Fordbarn will help. http://www.fordbarn.com/forum/showthread.php?t=67558&highlight=led relay brake lights Plus, consider using a relay. http://www.jalopyjournal.com/forum/threads/relay-ing-your-brakes-lights.798760/#post-8872185
Pretty easy to diagnose the switch itself simply by temporarily connecting the two wires together. If the brake lights come on then you need a switch. If they don't then you need to look further with the wires still connected until you find it.
Do yourself a favor and put a switch on the pedal instead of using the line pressure switch. The line pressure switches have been the cause of fires as the brake switch is usually hot all of the time. If the diaphragm leaks, brake fluid gets into the switch contacts and brake fluid is flammable. Ford started using them again in cruise control systems and vehicles started burning. If you do use the line pressure switch, make sure it's on a switched circuit so there is no power on it when the vehicle isn't running. No matter where you purchase the switch, it will be made in Mexico or China. It's just better not to put an electrical switch in a flammable liquid if you don't have to.
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