Topic: Brake light switch trouble shooting


rsh1950    -- 03-08-2016 @ 5:46 PM
  Subject: 1950 Ford Custom 2 dr v8
My brake lights do not work. Tail lights work just fine. This is what I did today to troubleshoot the problem. Pushed the brake pedal down with a 2x4, turned the key on. Then I got under the car with my circuit tester. Pulled the wires off of the switch and tested for power. No power on either wire. I tried tracking the wire to the firewall but I can't see where it goes.
Questions: Is there a fuse? Any recommendations for next step? Should I install a mechanical switch?

Looking forward to your feedback
rsh1950


CharlieStephens    -- 03-08-2016 @ 6:16 PM
  I am not used to working on the 50 but I will take a crack at it. One of the two wires should have power. You have now isolated the problem to the wire between where the power is picked up and the switch. Do you have a wiring diagram to see where the power pickup is located? As a very last resort if you can't trace the wire just bypass it with another wire, that would be a lot easier than adding a mechanical switch. I assume there is a fuse block in the car, have you located it and checked all of the fuses? Do you have an instruction manual for your car, there should be a wiring diagram in there?

Charlie Stephens

This message was edited by CharlieStephens on 3-8-16 @ 6:27 PM


deluxe40    -- 03-08-2016 @ 7:22 PM
  There is a wiring diagram in the back of the green Shop Manual for 1949-50-51. It shows a green wire running from the brake switch to a 14 amp fuse on the circuit breaker panel. On my '51 that panel is mounted on the inside of the dash between the clock and the speedometer, just about the hardest place to reach on the car. You might need remove the radio to get to it. The picture in the diagram shows the fuse mounted in a horizontal position in the lower corner of the circuit breaker panel on the side nearest the speedometer. The diagram also shows a bullet connector along that wire somewhere. It might be that it has just come undone. Look for the wire coming out of the top of the kick panel on the driver's side.


Drbrown    -- 03-08-2016 @ 8:18 PM
  As a safety feature, the brake light circuit should always be active, ignition key on or off.


rsh1950    -- 03-09-2016 @ 3:49 AM
  All, thanks for the quick feedback. I do have the green shop manual and I will look closer now with your input. I did not know that the brake light would work with the key off....live and learn.

thanks
rsh1950


TomO    -- 03-09-2016 @ 8:41 AM
  Look for the green wire at the circuit breaker, I don't think that the stop lights are fused. There is a connector between the switch and the source. It appears to be by the voltage regulator in the wiring diagram. I have circled the connectors in red.

Tom


Kens 36    -- 03-09-2016 @ 11:43 AM
  My good friend Tom is almost always right on the money. One minor clarification: the stop lights are definitely fused on the '50 Ford (I believe they went through the circuit breaker in 1951).

Under your dash up near the back of the clock you should be able to see a small panel with two fuses - I think they are 14 amp. One of those two fuses services the stop lights and possible another circuit. You should be able to reach the fuses, but they are not real simple to get to if you are not used to it. You do not need to remove the radio. Possibly one of your fuses is blown.

Ken


TomO    -- 03-10-2016 @ 7:14 AM
  Thank you for correcting me Ken. I am surprised that they did fuse the brake lights, due to safety concerns.

Tom


Drbrown    -- 03-10-2016 @ 8:36 PM
  I'm equally surprised they "fused" the brake light circuit. My '47 Circuit Breaker failed and burned-out the wire between my Circuit Breaker and my Ignition Switch, which feeds among other things, my brake light circuit. As well, the old glass-tube type fuses are prone to failure as their end-bases can overheat causing the fuse to fail.

This message was edited by Drbrown on 3-10-16 @ 8:38 PM


rsh1950    -- 03-11-2016 @ 2:14 PM
  Thanks to: Charlie Stephens, deluxe 40, dr Brown and Tom O for your input.

HOWEVER THE WINNER IS Ken 36!

THE FUSE WAS JUST WHERE YOU SAID IT WOULD BE AND BECAUSE MY CAR HAS NO RADIO IT WAS EASY TO GET AT. THE PROBLEM WAS ONE END OF THE FUSE HOLDER WAS LOOSE. I USED SOME SUPER GLUE AND NOW, I HAVE BRAKE LIGHTS AND AS A BONUS INTERIOR LIGHTS ALSO.
THANKS FOR EVERYONE'S INPUT.
rsh1950



Drbrown    -- 03-11-2016 @ 9:13 PM
  Ken 36 wins the free lunch at Hooter's ! That was the prize wasn't it ???

Glad it was not a big deal. If the fuse holder end was loose, check for overheating of it and keep an eye out to replace it.


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