Check the 50amp fuse in the fuse block if its okay-Do you see all the idiot lites that normally comes On? test for battery voltage on the Batt terminal of the alternator if you have it-the fusible link is okay-

Which of this links suit your problem: https://www.2carpros.com/articles/car-engine-will-not-crank-over or https://www.2carpros.com/articles/car-cranks-but-wont-start

Also see below see below

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I Checked all the fuse's in the fuse block. All fuse's are good. All the idiot lights comes on. The truck cranks, but it just won't start. i noticed that the security light comes on and then goes off after about a minute or so, but all the other idiot lights stay on. I'll check the voltage on the battery terminal tomorrow. Thanks. I'll get back with you.

I'll be waiting-Good Luck-Curiosity, How are you checking the fuses-eyeballing it, if so use a circuit tester and probe both ends of the fusible link the lite will lit up both ends-if not the link is open-

battery voltage is 12.6. I checked the fuses by pulling them out and eyeballing them. If no break in the line then I put them back. I'll check the fuses with a fuse tester. Or maybe it would save me time to just replace all the fuses. I'll get back. Thanks again.