67 Turn signal switch wiring

Let's say you knew nothing about this switch, and nothing of the wire colors. It is easy to figure.

What you have is

1...one wire for brake power coming in

2...one wire for signal flasher power coming in

3....one wire for left rear brake

4....one wire for right rear brake

5....one wire for left front brake

6 one wire for right front brake
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With switch centered, the brake power in is connected to both rear lamps

Flasher power coming in is isolated. Both fronts are isolated

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With switch left, flasher power in is connected to left front and left rear

AND brake power in is ONLY connected to right rear

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With switch right, flasher power is connected to right front and right rear, and brake power in is only connected to left rear

Start with the switch in center. In this position, the brake power coming in is connected to the two rear signal/ brake lamps. So there will be 3 wires only that show continuity. Temporarily label them.

Now you need to determine what is flasher power versus brake power, versus front lamps

Make notes as you go and eliminate what doesn't "compute." Just use process of elimination.