As I needed to add yellow/orange rear turn signals, I looked into the turn signal switch for some time now. Lights are hooked up and working correctly.

The '70 schematic (also in my signature) is not really showing the logic on a first glance, but I think I sorted it out. I plan on documenting all my car-related stuff, so I'd be happy if somebody could have a second look if what I came up with is OK:

Turn signals off, brake switch (white) gets connected to both rear brake/turn signal lights:



Turn signals left, brake switch (white) gets connected to right rear, flasher (purple) to left front and rear light:



Turn signals right, brake switch (white) gets connected to left rear, flasher (purple) to right front and rear light:



Educated guess: The hazard flasher, when activated, connects the hazard flasher relay output (brown)

* directly to bright blue and dark blue for the front turn signals
* to white to feed the rear turn signals via the "brake switch" input.

So braking with the hazards on will override the rear and front hazard signals with a constant 12V via white.

Correct? Brain farts detected?

 

That sounds right, but I will admit that I never tried to trace out exactly which part of the switch connects to which other part at which time.

To run separate rear signal lights, all you do is connect the feeds for the front signal lights to the new rear signals.

- Eric

 

This way the rear original/red turn signals will continue to flash and with additional hazard flashers active the brake logic will override the flasher can and connect front and rear turn signals: Hit the brake and all 6(!) turn signals will stay lit without flashing.

I had to

* tap the front turn signals for the orange rear ones (as you said)
* wire the rear "bright" filaments to the brake switch only
* unhook the hazard flasher from the brake switch to avoid constant 12V to all turn signals while braking - only pulsed power through the hazard flasher relay at all times.

That's another story. Maybe it's time for a "Destroying your wiring for German post-1970-car registration conformity" How-To?

Ed:

Just check: Switch on the hazards and step on the brake - your front turn signals will stay on.