Dead battery This is the most common reason your vehicle won't start
First, check all of the battery terminals to make sure all plugs are intact and attached clear of debris. If you do see loose fuses or a corroded battery terminal, re-plug and clean off the terminals and try again.
Bad ignition switch If your battery is fine but your starter is still silent and the vehicle won't even click, it could be a bad ignition switch. If the warning lights on your dashboard won't light up and your battery is clean and the connections are fine, it is likely the ignition switch. A quick test to do this is when you start the car, check if the dashboard lights dim a significant amount or turn off completely. If they do, your ignition switch is OK.
Bad starter connection A bad starter connection can be caused by corrosion, similar to the battery. In fact, if the battery is corroded if can affect the electrical equipment, such as the starter.

Possible bad ignition switch. Check wire going to starter for 12 voltage