Keyswitch not sending power to the solenoid

[1Byounkin]

I have a problem that just pop up. All at once if you turn the key to start the starter would never turn. Every relay clicks like normal. You can turn the key to ON and touch the two post, which would start it fine. If I put a test light on the wire (slide on) that is from the key switch, you would get nothing when the key is turned. Yes one side of the solenoid is hot, like it should. And you can all so jump each post (big post) or Hot post to the small post (from the key switch) and the solenoid would kick just fine. I belive it's something in the start circuit.

What is the best why to trouble shoot this?

 

[1993Saturn]

Sorry I didn't see this sooner. I'm too busy with my own project right now. So, you connected a test light to the IGN wire coming off the IGN switch and you got no start signal. A different test to see if the switch is the problem is there are 2 other wires (sorry, can't remember the colors) that shut off when the key is turned to 'Start.' At the same time, there is one wire that remains hot when the key is turned to the 'Start' position. These 3 wires become hot at the 'Run' position of the key (what the key rebounds to after starting). You do have one hot at all times, right?
Let me know how this part is before we move to the rest of the circuit.
OK?

 

[Mudboy]

do you have an aftermarket alarm?