My 1998 Ford Ranger Will Not Crank Over, Have Power, The Lights And Radio Work What's Wrong?

With the shifter in neutral, take a screw driver and touch between the small terminal on the starter soliniod and the larger terminal that goes to the battery. If the motor turns over the problem is either the clutch interlock switch or the ign switch. If it does not turn over have some one turn the key and hit the starter with a hammer. If it starts now the starter brushes are worn, If still nothing touch a large screw driver across the two large terminals on the starter soliniod. If it starts now the soliniod is bad.

Have you checked starter solenoid

Clutch interlock switch

It could be connection problems, bad starter solenoid, or even the starter if this is a standard transmission. Only one other answer for automatic transmission is the Safety neutral switch. There is only one other thing it could be is the electric switch on the column.

Just had this problem with my 96 Ranger. Hard one to troubleshoot (time consuming and frustrating anyway). Test the easy things first because after three days my problem turned out to be a 5 minute fix and where I started!
Posible Problems:
Wiring - Start at the Starter and follow back to the big wire back to the battery and the smaller back to the starter relay (my problem was a bad spliced wire from a previous mechanic extending the starter wire and unfortunately I overlooked it)
Ignition Switch - If you hear a Click/Clunk when you turn the key; your ignition switch is good.
Starter/Solenoid (all in one on 95 and up) remove three bolts and two wires and take it to autozone or other auto store for a free test. Can save you a $100 bucks and it is free troubleshooting.
Starter Relay - Other than using a multimeter and a friend (think about safety please) to make sure you have power getting to your small starter wire it is what is making the click/clunk nose when you turn the key. Buy a manual to help you do this test.

Check the EGR sensor. They sometimes burn up and everything else is fine- battery, alternator, starter, fuel pump, etc. It's about $50 and very easy to take off and replace. It affects the air flow and if it went out it will cause a starting problem.