Security is blinkn on my dashboard and car want crank what can i do?

Ali, when you say won't start, do you mean it will not even crank, or does it crank and does not fire? Sounds like a computer or security issue .
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I assume not cranking? Or cranking, but not starting?
No other work done while battery disconnected?

The security, antitheft or lock picture/icon is a visual indication that something in the car's antitheft system is failing. In most GM cars and trucks there is a hidden system that most people are unaware even exists. From the moment you put your key in the ignition, there begins a constant line of communication between your key's security chip or transponder, to the ignition's lock cylinder, and then to the car's TDM (Theft Deterrent Module). These 3 parts are in CONSTANT communication. If the key is in the ignition, then these parts are sending signals to each other. The security light illuminates when that signal gets broken, even just for a second. When the signal breaks, the car misinterprets this as an attempt at theft and goes into antitheft mode. The car thinks its being stolen or hotwired because it is not getting that signal from YOUR specific key. This is why the security light turns on and shuts down your vehicle. This link explains it pretty well.
http://vatspasslockpasskeysecurityhelp.yolasite.com/

If the lights work but no crank, it could be the security system or the neutral safety switch among other things.
Is the security light on or flashing ? Do the warning lights come on when you turn the key on ? Did you try cranking it in neutral ?

It turned on because there is something failing in your antitheft security system. If you would have stopped the car and tried to restart it, it would NOT have cranked over due to a starter immobilizer. Go to this link fort everything you need to know.

http://vatspasslockpasskeysecurityhelp.yolasite.com/

I have this same problem. Evidently there is some sort of malfunction in the security system. You have to put your key in the ignition and turn it on "on" for approximately 10 minutes. The security light will stop blinking, then go off. Turn the igition back to off. Now you should be able to crank the car. I have contacted alot of people about this and the only answer I get is they will not do a recall because it is not a life threatening situation.

Sounds like a generic security system problem. If it doesn't happen again, then don't worry.

However, if it happens again, have the dealer try to duplicate the problem. I know this is hard, but it's a statistical thing.

Hope this helps.

Try turning the key to the on postion-not crank, just to he postion right before cranking. leave it in that postion for 15 min, Do this three and after the third time go ahead an try to start it. Hopefully this will reset your security for you.

you probably have a broken wire in the ignition that reads the resistance in the chip in the key. there are two wires that attach the ignition switch to the security system.I had the same problem and it can be easily fixed by putting a resister in place of the chip in the key.any garage that puts alarm systems in cars will be able to do this very easily and very economically.