Okay, your probes are in their correct locations so don't change those. Turn on your meter and then turn your dial to the bottom one that is just to the right of the 200 symbol. Should be nine clicks to the right.
That is continuity. Now when you touch your two probes together it should beep. That means your puting power from your meter through your meter. So touch anything metal with both probes....it should beep. Do not touch anything that has power. Continuity is always done with no power hooked to it.
So if you take a blank wire right now and touch both ends than if it beeps than that wire is good. (Your sending low voltage through the wire with the meters battery power)
So then find the two ends of your kill switch. Put one probe at the end of one wire and the other probe at the end of the other wire. Without the button pushed it should not beep. Keep the probes touching those wires and push the button....it should now beep.
Maybe play with your old kill switch first if you still have it.
Here is a video and near the end he shows you continuity.
Report back for further instructions or that you found your problem.
