Just a couple hours in the garage tonight, so not a lot to report. This morning, I purchased some 12v bulbs from the local auto store to test the turn signals and hazard circuits. They both tested “sat” as we used to say in the navy – i.e., they both worked fine. They blinked like a charm.

I was curious why you need to actually load the flasher circuits to see the blinker function. What I learned is that old-school blinker relays contain an electro-thermal mechanism that requires at-load current to operate properly. Apparently, inside the cylindrical “flasher” housings are three components:

• An electrical contact that conducts electricity into the wire
• A piece of gently curved spring steel to which the electrical contact attaches
• A resistive wire wrapped around a smaller piece of spring steel

When you activate the turn-signal relay, the thermal flasher connects to the turn-signal bulbs, allowing current to flow. Initially, the conductive spring steel does not touch the contact, so the only thing that draws power is the resistor. Current flows through the resistor, heating up the smaller piece of spring steel but sending very little current to the lights. After a pre-set amount of time (e.g., ½ to 1 second), the smaller spring steel component heats up enough that it expands and straightens out the larger, curved piece of spring steel. This forces the curved spring steel into the contact so that current flows to the lights unimpeded by the resistor. At that point, with almost no current passing through the resistor, the smaller spring steel quickly cools, bending back away from the contact and breaking the circuit. The cycle then starts over and repeats, creating the familiar "clicking" sound we all have come to recognize as a blinker. 100-year-old technology, but still ingenious!

Here's a fuller explanation: https://auto.howstuffworks.com/turn-signal2.htm

I had no idea that’s how a flasher relay works, and I’m not even entirely sure if that’s how the FFR-supplied relays work. But now that I know, it makes sense that you need to load the circuit in order for it to operate correctly. In any event, I was really happy to see my turn signals and hazard lights working properly. One more thing crossed off my punch list.

The other thing I did was wire a “flash to pass” function using the push-button on the RT stalk. I used a generic Dorman 88069 30A 5-pin relay purchased from Amazon: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1.

I wired it pretty much as Russ instructs. I attached one of the black wires from the VW stalk to ground. I attached the other to pin 85 on the Dorman relay. I cut the “LT BLU-HDLT SW/ DIM SW” and made it into a three-way pigtail. I attached two of those leads to pins 86 and 87 of the Dorman relay and the other to the high-beam toggle switch in my lower dash support. In essence, this uses the 12v headlight power to (1) trigger the Dorman relay when the stalk button is pressed, and (2) send line voltage through the relay (when activated) to the high-beam circuit. Finally, I connected pin 30 of the Dorman relay to the two-brown-wire output of the high-beam toggle switch. This momentarily powers the high-beam circuit when the stalk button is depressed, while leaving the low-beams on. In other words, “flash to pass.”

I hooked up a 12V bulb and tested it out, and (to my pleasant surprise) it worked perfectly the first time:



Paul is right, wiring is fun (when it works). At this point, I can comfortably state that the Russ Thompson turn signal system is relatively easy to install both mechanically and electrically (at least for the turn signal and flash-to-pass functions). And his instructions were 100% accurate.

Progress continues . . .