Fixing the factory turn signal flasher


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Philadelphia, PA
I'm getting my 78 ready for inspection this year and as luck would have it, the turn signals starting acting wonky, sometimes working, sometimes not and sometimes just steady on. I read through a few threads here and like others, mistakenly thought it was a standard three prong flasher. The threads on here clued me in it was not and that some magic is installed in a 2 prong flasher for the auto-cancel. So figuring I had nothing to lose, I carefully disassembled the flasher and was able to see the inner workings, but also clean the contact points and get it working again. To disassemble, cut off the plastic wrap, then gently bend the housing peens back to round. Gently work the board out, but don't yank it violently, there is a wire connected to the top and that piece doesn't seem to come out (glued?). There is also an alignment V notch pointing to the center terminal.

In the pictures below, you can see the various parts, but also that in the top of the unit is the "magic". A little black box that has one wire straight through to it, but it must also be connected to the housing because on the one leg of the two prong flasher circuit is some cooper flashing that will contact the housing when re-assembled. This must be the control to stop the flasher. Which knowing this now, maybe someone could use just that black box piece from the original flasher along with your LED lights and two prong flasher to have it start auto-cancelling again.

To clean the contacts, I just pushed down gently on the large center piece and used some fine sand paper between the small contact points, as well as between the center solenoid and the large center plate. Signals are working great now, better than before too as in the past, it always took a little heat into everything to have them flash. To reassemble, I just slid it back together, then gently peened the housing back inward to clamp the board.