Having a little bit of trouble with my column switch, the little switch assembly is really fussy. To help troubleshoot I decided to actually figure out how that little mystery switch works, and what is what.

Seeing as it's a hit and miss on the web, I created a diagram for us showing how the contact pins and springs relate, and to which wires they connect in the curved harness plugs.

At least with this you could quickly find, power and troubleshoot the feeds out to the bulbs from the dash plug, and test the switch. Note: on the body side of the harness, the signal indicators in the cluster are connected to the L/R front signal outputs. On Taiwan, the left front signal could be light blue.

So, in a nutshell,

When applying the brakes, contact is made at the brake switch, sending current through the Black/White wire to pin A. Both rear brake lamp pins E/F are in constant contact with A through their respective pins, so applying brake feeds both simultaneously.

Applying left signal moves the E pin spring off the A feed pin(brake switch) pin, and into contact with the B feed spring. Then both springs contact the front signal lamp output pin C. Now front and back left signals are fed off the flasher unit.

The same happens when selecting the right signal. Signal applied when braking, the one signal side selected disconnects from the brake switch and is fed from the flasher. The other brake lamp stays fed from the brake switch.

Now I can get to work on mine. Anything to add, please do. cheers.