2000 Alero Security light flashing and wont start

Is the vehicle getting any fuel?

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://www.diy-gm-security.com/

Here is a link that can help you with the bypassing of your Passlock antitheft system. http://vatspasslockpasskeysecurityhelp.yolasite.com/

My security light isn't blinking even after the 30 min relearn it's just stays red?

Rule of thumb, when the security light flashes, thee problem will be in the key or ignition. When its solid, its probably the theft deterrent module. TDM. This link might help you understand the problem. http://vatspasslockpasskeysecurityhelp.yolasite.com/

SOUND LIKE THE THEFT SECURITY PROBLEMS. MOST OF THE TIME.THE IGNITION KEYS OR IGNITION SWITCH KEY LOCK CYLINDER WORN WHERE THE BCM AND PCM DONT RECOGNIZE KEY OR SWITCH SIGNAL.SO THE BCM AND PCM WILL GO IN THEFT SECURITY MODE.THE DEALERSHIP WILL HAVE TO FIX.BECAUSE IF THE KEYS , IGNITION SWITCH AND LOCK CYLINDER AND BCM HAS TO REPLACED.THEY WILL HAVE TO BE REPROGRAM USING DIAGNOSTIC EQUIPMENT. NOT A HOME FIX.YOU WILL NEED TO GET FIX SOON AS POSSIBLE.BECAUSE FAULTY SECURITY THEFT CODE WILL SHUT DOWN VECHICLE FUEL SYSTEM WHILE DRIVING OR IT WILL GET TO A POINT WHERE CAR WONT START NO MORE.THIS FIX WILL COST ABOUT $600.00.

Most likely you replaced the starter because it wouldn't crank over. If this is correct and the security light was flashing before replacing the starter, then most likely you have a problem with the pass-lock system. If your ignition cylinder is located in the dashboard, you will need to remove it and replace the passlock housing.

replace passlock sensor and then relearn security

if your security light flashing it will not start. you let it flash for 10 to 15 min then it should stop. turn the key off then try to start the car. if it does start you need a ignition lock cylinder

When the vehicles security light is flashing and the car won't start..put the key in the ON position and wait until the security light stops flashing and then turn OFF and then start. this is from a security glitch and it shuts down the gas so car won't start. Good luck!!