Haven't done anything on it today, will try it in the freezer tomorrow. My car is an autotragic, by the way.

I put the switch in the freezer for a bit, and now I have continuity through the switch. Pretty sure it will open again when it warms up. I'll see if I can track the wiring tomorrow if it can be done without too much collateral damage.

I did some more searching, and @Zed Head looks to be right about the switch being for the dual point distributor. The challenge is that it doesn't show up until the 72 FSM on page EC-11. I found a thread here: https://www.zdriver.com/forums/240z-260z-280z-performance-technical-124/thermal-relay-question-36814/ that shows.

The temperature range and continuity check you did fits with this chart.

And the FSM said it was introduced in 71.

Go to the Downloads in the Resources section to get the 72 FSM.

 

Thanks guys, that makes sense. I was running the dizzy with only one of the points, so the thermo-switch connection to the missing points must be tied up somewhere. Going to track it down just for laughs.