Announcement

Collapse
No announcement yet.

turn signal and brake light woes

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • pkingco
    Experienced
    • Nov 9 2021
    • 245

    turn signal and brake light woes

    Hi all. I'm close to putting the 59 convertible on the road (plates are on the car!). But I'm having trouble with the turn signals and brake lights. I had turn signals working before, but now I get nothing on either side. Parking lights/tail lights/headlights all good. I checked the fuse on the light switch: good. What procedure should I follow to hunt down the problem?

    Re: the brake lights, I have only the passenger side working now. Both were working before. And the brake light(s) stick on when I release the pedal. I have to remove one of the wires on the brake light switch to turn them off. When I reconnect the switch, lights stay off.

    Any thoughts on these issues would be greatly appreciated, as always.



  • jopizz
    Super-Experienced


    • Nov 23 2009
    • 8460

    #2
    It sounds like you have multiple problems. The sticking brake lights could be the stop light relay in the trunk. I would check that first. I doubt it's the brake light switch since the lights stay off when you reconnect it. Your car as two different brake light circuits. The inner lights come right off of the relay and are tied together. If one light doesn't work then it's either a wiring problem to that light or a bulb/socket problem. The outer brake lights are independent of each other and come off of the turn signal switch on separate wires along with the turn signals. If the turn signals don't work at all check the flasher first. If that is good then you may have a turn signal switch problem. Do the turn signal lights come on at the instrument panel and stay lit? As always follow the wiring diagram.

    John
    John Pizzi - Squarebirds Administrator

    Thunderbird Registry #36223
    jopizz@squarebirds.org 856-779-9695

    https://www.squarebirds.org/picture_gallery/TechnicalResourceLibrary/trl.htm

    Comment

    • pkingco
      Experienced
      • Nov 9 2021
      • 245

      #3
      Thanks, John. The turn signal lights do not come on at the instrument panel now. They did both work. I'll check the flasher and look for that brake light relay.

      Comment

      • pkingco
        Experienced
        • Nov 9 2021
        • 245

        #4
        Well, the driver's side bulb socket had a bad connection, so that solves the one brake light. But I need to correct my previous observation— the brake lights do not turn off when I cycle the connection to the switch. They come back on when I reconnect it. I checked for a relay in the trunk, but do not have one.

        Re: the directionals, I removed the flasher and tested it, and it is working fine. I removed the fuses on the light switch and tested both for continuity and they are fine. I tested for power from the orange/yellow wire that runs from ACC terminal to the flasher, and could not get a reading. But the orange/yellow wire is connected solidly to the ACC terminal that also has radio and heater, which both work. Seems unlikely that it is a bad wire, since directionals were working fine before.

        Any further thoughts?

        Comment

        • jopizz
          Super-Experienced


          • Nov 23 2009
          • 8460

          #5
          Originally posted by pkingco
          But I need to correct my previous observation-the brake lights do not turn off when I cycle the connection to the switch. They come back on when I reconnect it. I checked for a relay in the trunk, but do not have one.
          It sounds like your brake light switch is bad. Either that or your brake push rod is adjusted too long.

          Testing the orange-yellow wire is pretty simple. Remove the wire at the light switch fuse and test it with your voltmeter. That's the first point of contact after the switch. If no power there then it has to be either the wire or the connection at the ignition switch. It's important to isolate the wires from the light switch and flasher so you are not introducing more points of failure. Don't assume anything. Trust your meter and work your way from the ignition switch to the light switch to the flasher. Unless it's a new harness broken wires are very common after 65 years.

          John
          John Pizzi - Squarebirds Administrator

          Thunderbird Registry #36223
          jopizz@squarebirds.org 856-779-9695

          https://www.squarebirds.org/picture_gallery/TechnicalResourceLibrary/trl.htm

          Comment

          • pkingco
            Experienced
            • Nov 9 2021
            • 245

            #6
            Thanks, John. I do have all new wiring harnesses, but I will check that. Re: the brake light issue, is it possible to adjust the brake push rod without dropping the pedal assembly? A simpler test will be to test the switch, but I am suspecting the rod.

            Comment

            • jopizz
              Super-Experienced


              • Nov 23 2009
              • 8460

              #7
              There's an eccentric adjuster on the pedal to adjust the push rod. Refer to the diagram.

              John

              59 brakes.jpg
              John Pizzi - Squarebirds Administrator

              Thunderbird Registry #36223
              jopizz@squarebirds.org 856-779-9695

              https://www.squarebirds.org/picture_gallery/TechnicalResourceLibrary/trl.htm

              Comment

              • pkingco
                Experienced
                • Nov 9 2021
                • 245

                #8
                Thanks, John. The clutch pedal in mine complicates things. I can't see any way to get to that eccentric without some dismantling. Will see if I can sort it out.

                I got the directionals working. It turns out the new harness bypasses the light switch with an inline fuse holder. Fuse was blown.

                Comment

                • jopizz
                  Super-Experienced


                  • Nov 23 2009
                  • 8460

                  #9
                  I would just put an ohmmeter on the brake switch and loosen it. If it stays shorted then it's not the push rod.

                  John
                  John Pizzi - Squarebirds Administrator

                  Thunderbird Registry #36223
                  jopizz@squarebirds.org 856-779-9695

                  https://www.squarebirds.org/picture_gallery/TechnicalResourceLibrary/trl.htm

                  Comment

                  • simplyconnected
                    Administrator
                    • May 26 2009
                    • 8829

                    #10
                    Be careful with the brake switch wires because one is always hot. Pull one of the wires off the brake switch and see if your stop lights go out.
                    (We commonly short both brake switch wires to test the lights to simulate someone standing on the brake pedal.)

                    With the wires off the brake switch, if your stop lights don't go out, they are getting power from another source.
                    If they do go out, something is energizing the brake switch or it's a bad switch as John said in post #5.
                    Did anyone work on the Master Cylinder? - Dave
                    Member, Sons of the American Revolution

                    CLICK HERE to see my custom hydraulic roller 390 FE build.

                    "We've got to pause and ask ourselves: How much clean air do we need?"
                    --Lee Iacocca

                    From: Royal Oak, Michigan

                    Comment

                    • pkingco
                      Experienced
                      • Nov 9 2021
                      • 245

                      #11
                      Thanks for that, Dave and John. Still having the issue with the brake lights. I replaced the switch—path of least resistance—and the lights still stay on after depressing the brake pedal. But only when the car is running and pressure builds up in the system. I can pump the brakes all day before starting and the switch works fine... lights come on and off. So I'm quite sure the issue is the rod length. Because reaching the eccentric bolt is going to require removing seat, the lower dash trim panel, which in turn requires removing the overdrive cable from the manual transmission and pulling it out completely (because the replacement cables don't have any way to remove the lock nut at the end of the cable to free the trim panel), and lowering the steering column to see if I can gain access, I'm first going to try an experiment. I'm going to shim the back of the master cylinder out and see if that solves the problem. If so, I will know it is the rod length.

                      If you have any other thoughts, please let me know. Many thanks.

                      Comment

                      • pkingco
                        Experienced
                        • Nov 9 2021
                        • 245

                        #12
                        Well, I ended up removing the seat, dismantling the console and under dash valance and loosening the steering column to see if I could gain access to the eccentric bolt on the clutch/brake pedal assembly, but to no avail. So I followed the tip Dave provided me with (Thanks, Dave!) and made a bracket for a momentary switch and installed it on the brake pedal arm. It just comes into contact with the under dash booster when the brake pedal is depressed and brake lights now work like a charm.

                        IMG_3779.jpg

                        Comment

                        • jopizz
                          Super-Experienced


                          • Nov 23 2009
                          • 8460

                          #13
                          You have to wonder why Ford didn't do that in the first place. It's certainly more reliable than the hydraulic switch.

                          John
                          John Pizzi - Squarebirds Administrator

                          Thunderbird Registry #36223
                          jopizz@squarebirds.org 856-779-9695

                          https://www.squarebirds.org/picture_gallery/TechnicalResourceLibrary/trl.htm

                          Comment

                          • simplyconnected
                            Administrator
                            • May 26 2009
                            • 8829

                            #14
                            ...which begs the question: Is your master cylinder's piston retracting far enough for brake fluid to return to the reservoir? If not, you stand the chance of having your brakes lock up. When DOT-3 gets hot it expands, exerting more pressure on the brake shoes and in turn it turns the brake light switch on.

                            I love the idea of a mechanical brake light switch on the pedal. If you aren't running the current through relay contacts, I suggest you do so. You can keep the setup you have but let the switch turn a relay coil on. Then, let the relay contacts control your brake lights. Your switch will never burn up from overcurrent. This is how I was able to use a computer mouse switch to run my lights. - Dave
                            Member, Sons of the American Revolution

                            CLICK HERE to see my custom hydraulic roller 390 FE build.

                            "We've got to pause and ask ourselves: How much clean air do we need?"
                            --Lee Iacocca

                            From: Royal Oak, Michigan

                            Comment

                            • simplyconnected
                              Administrator
                              • May 26 2009
                              • 8829

                              #15
                              Finally... a solution to the confounded brake light switch problem:

                              image.png​ - Dave
                              Member, Sons of the American Revolution

                              CLICK HERE to see my custom hydraulic roller 390 FE build.

                              "We've got to pause and ask ourselves: How much clean air do we need?"
                              --Lee Iacocca

                              From: Royal Oak, Michigan

                              Comment

                              Working...
                              😀
                              🥰
                              🤢
                              😎
                              😡
                              👍
                              👎