Anti-thief system cut off power to den gine an won't cut it back on

Try to disconnect the battery cables, wait for 2 minutes and reconnect back the battery cable and see how.

Your chipped key is not making a good connection to your factory installed anti-theft device. Lightly grease both sides of car key with electric bulb grease and work it into key ignition. Over time the key wears down, contacts in ignition switch become worn and corroded. Grease makes better contact...chipped key is able to send signal to factory anti-theft device which unlocks all systems required to start you engine. Make sure the key you are using is a chipped key for your car; not a un-chipped cut key from the key cutting machine. It will work on locks, but only a chipped key for your car will deactivate your anti-thief and you get power to your engine and systems to get it started.

This is the anti-theft system working properly. The vehicle has lost communication with the key and it this causes it to go into theft mode. This can happen randomly, or if the battery in the vehicle was replaced. Unfortunately this means a trip to the dealership to have them reprogram a key.

You can check the starter if it don't start take a hammer in hit the front of it then try to start it if it starts you know it's the starter next time it would help to know the make and year of the car if you can get to the starter if not have it check at a shop

2005 ford
My personal suggestion would be to go for these repair catalogs. I know this website reliable-store that i used to buy them from, and they sold online it was very good manual. Go ahead, I bet.

No it can't be bypassed.

The first thing to do get it checked for DTC'S - diagnostic trouble codes . Not at auto zone or any other parts store , you want to have full scan of all the modules on the car. Don't know how much you know about automotive electronics , computer controlled systems etc.... Your vehicle has at least 10 modules (computers ) on board , there all talk to each other on a serial data network . C.A.N - controller area network . Or in the case of GM it has it's own . GMLAN -
How to Diagnose Controller Area Network CAN When you turn that ignition switch to start it is an input to the computer ,be it the PCM or BCM ..

Hello did you checked the security system for your car Because the new cars have anti-thief system check it with your car company. i am sure it might help. Please rate my comment thanks

Check the anti-theft module and relay

It sounds like it may be a problem with the PATS (Passive Anti Theft System). Chevy has been having problems with PATS since 1992 til current. Even if your key doesn't have a visible "chip" in it, it is possible that you have the PATS system. The newer PATS systems work by recognizing the exact cut of the key. In some cases extremely worn out keys have been known to stop working correctly with your ignition. In worst case scenarios the ignition cylinder itself, which contains the other chip for PATS, wears out so badly that, one time in ten or more your vehicle doesn't recognize the key and fails to start. The logic is this: If a thief tries to jimmy the ignition, the PATS system shuts down the ignition system for 20 minutes (30 on some vehicles). This is supposed to discourage the thief from trying again, while still letting you start your vehicle. There are procedures for bypassing the PATS system on many vehicles, but it is not for the faint of heart. The wiring work itself isn't bad, but there are catches: 1) you must have the vehicle running while you make the modification in most cases, and not shut it off during the bypass. 2) It's recommended you install a switch in the bypassed wire so you can disable your bypass in case your vehicle needs service. 3) if the vehicle dies during the bypass for some reason, you may have to visit the dealership and get a new ignition cylinder, and a quick reprogram of the PCM or ECU to get it going again. (Pricey)