You may have the wrong solenoid. The engineers couldn't make up their mind. There's at least three different starter circuits, and three versions of these solenoids. One has a single smaller terminal. 12 volts to that will make it engage, but it has to bolted to the body for the ground. The second version has a second smaller terminal that gets 12 volts switched onto it when the solenoid is engaged. That is to bypass the ignition resistor during cranking. If you don't have an ignition resistor, that second terminal just isn't used. On the third version, there are again two smaller terminals but while the first one still gets 12 volts from the ignition switch to activate it, the second terminal has to go to ground, and it does that through the neutral safety switch.
As I recall, your truck should have the ignition switch and the neutral safety switch in series going to a single small terminal on the solenoid. There is no second smaller terminal, or, if there is, it isn't use. Remove the wire plugged onto that small terminal, then use a jumper wire to jump from the battery positive terminal to that small terminal on the solenoid. The solenoid should engage and the starter should crank the engine. Don't have the ignition switch on and the transmission in gear because the engine could start, and you'll look funny chasing after your truck!
Thursday, March 19th, 2015 AT 6:23 PM