The Hall Effect Vane Sensor is a fairly complex component. One of the results of this is that the tester can be very simple. By far the most difficult part is finding the connector to allow it to connect to the ‘Bean Can’ wire. Here is the schematic:-
It’s worth mentioning that the switch and the test button are not strictly necessary… there is no current drain when the unit is not in use. I also used a two pole switch because that was the most suitable one I could find. A single pole switch would b equally as good.
I’m not going to give detailed building instructions, this project is so simple that they aren’t necessary. Here is a picture of the finished article: