Crank shaft position sensor, how to test for power?

That sensor doesn't get power, it is just a coil that generates a sine wave from the teeth on the reluctor passing the coil's tip. If you have an oscilloscope, you could watch the signal, but a common meter won't tell you much because it doesn't sample fast enough.

Well new tool time.

Many thanks.

If you are looking at tools, take a look at the U-Scope from AES Wave. It's a nice compact single channel scope and is very handy to have. The basic kit is a great starter item.
Mine gets used a lot and I've added a PICO as well. However, if you can find an older Snap-on tool (like the Vantage, modis, solus and others) that has a scope those work pretty well and sometimes for less than the PICO.