Prowbar
August 16th, 2023, 09:50 PM
The turn signal cam broke a long time ago on my GMC.
After finding dozens of threads about the turn signal cams breaking and without any simple solutions, I found a method to easily repair them. See pictures.
I used a coiled leaf spring that is used in an (older) electric motor to press the carbon brushes onto the rotor. The center of the spring has a folded tab, which can be used for the cam part. The width of the spring is close enough that it needs no modification.
I unwound the spring, cut it off, and fitted it to the proper length. I then used a small carbide PCB drill to drill a small hole in the spring, which was then enlarged with a 2,5mm (.100") drill. A smaller hole was then drilled in the top of the cam, where the arrow is pointed. A small screw, used in consumer electronics, was used to fasten the leaf spring to the turn signal cam. I only used one screw, and it seems to work fine.
That spot was chosen because the plastic is solid there, which allows for a strong connection. It is best to predrill the hole to avoid unnecessary tension on the plastic. Experiment to find the right size first. In my case, it was a 2mm hole (0.080")
I then tested it for function and it works fine! I reassembled the steering column without any trouble. The turn signal cam works and cancels the turn signal as it should again. Anyone with a bit of mechanical skill should be able to fix their turn signal cam this way.
After finding dozens of threads about the turn signal cams breaking and without any simple solutions, I found a method to easily repair them. See pictures.
I used a coiled leaf spring that is used in an (older) electric motor to press the carbon brushes onto the rotor. The center of the spring has a folded tab, which can be used for the cam part. The width of the spring is close enough that it needs no modification.
I unwound the spring, cut it off, and fitted it to the proper length. I then used a small carbide PCB drill to drill a small hole in the spring, which was then enlarged with a 2,5mm (.100") drill. A smaller hole was then drilled in the top of the cam, where the arrow is pointed. A small screw, used in consumer electronics, was used to fasten the leaf spring to the turn signal cam. I only used one screw, and it seems to work fine.
That spot was chosen because the plastic is solid there, which allows for a strong connection. It is best to predrill the hole to avoid unnecessary tension on the plastic. Experiment to find the right size first. In my case, it was a 2mm hole (0.080")
I then tested it for function and it works fine! I reassembled the steering column without any trouble. The turn signal cam works and cancels the turn signal as it should again. Anyone with a bit of mechanical skill should be able to fix their turn signal cam this way.