To troubleshoot an ignition switch in a vehicle, first open the fuse panel under the steering wheel column, and find and remove the fuse for the ignition starter by using the diagram on the fuse panel cover. Use the fuse puller inside of the fuse box. Check whether the metal strip in the fuse is broken or damaged. If it is, replace the fuse with a new fuse that has the same amperage.
If the metal strip is intact, check under the hood of the car. Set a voltmeter dial to Volts, and touch the red lead of the meter to the battery's power terminal. Next, touch the black lead of the meter to the battery's negative terminal. A healthy car battery shows 12.4 volts on the voltmeter screen. If it says otherwise, the problem is likely the battery.
If the battery is charged, turn the ignition key to the three position to turn the engine over. If it does not turn over and there is no clicking sound coming from the steering wheel column, the ignition switch is dead and must be replaced. There is no measurable service life for an ignition switch, and they occasionally die without warning.