Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
I have a 1990 toyota corolla that is having a crank no start issue I have followed your videos on how to test the issue and have come to a road block so I was checking the distributor with a test light as you have shown and when I check the wiring harness with the car in the on position I'm not getting any power to any of the wires I have attempted to search for a diagram to figure out which wires should be showing power but have been un successful and was wondering if you could point me in the right direction to solving this issue please