how do i start the truck when the anti-theft light is on all the time?

The same thing happened to me after many months of troublesome problems. Every-time I had the dealership perform a diagnostic test on my truck, the problem would go away. However, after some research, I was able to repair it myself, at home, but the repair was very involved. It involved pulling the air bag, pulling the steering wheel with steering wheel puller and then dropping the steering column down. I had to disconnect the battery first and let my truck sit for a couple of hours before I could disconnect the steering wheel air bag safely since a capacitor is involved which is located on the BCM. Otherwise, the air bag could accidentally explode in your face severely injuring you. After I did all this, I pulled and replaced the ignition key switch housing switch (security module) which was a real pain. When I replaced the "security module", I had to take the lockset out of the old module and replace it in the new module. That wasn't too hard though compared to all the other steps involved. The Security Module Switch cost me around $75.00 dollars to replace which wasn't too bad compared to what the labor would have cost me. I figured that I saved anywhere from $250.00+ to $300.00+ dollars in labor fees by doing this repair myself. If you don't feel comfortable doing this repair, I would suggest having your truck towed to a reliable automotive repair shop or to your dealership and let one of their mechanics replace this switch. This is not your average DIY home mechanic repair, so beware! Good luck!