Security system?

I have a friend with a 98 firebird v-6 that won't start. The same problem occured a few months ago and I guess it was a security system problem so he had the system disabled. Now he's having the same problem. It won't turn over and there's no click or anything. Could the security system turned itself back on? If so how could you disable it again so he could at least get it somewhere to be fixed?

How was it disabled? If it it was through the ECU tehn yeah, it came boack up. Friend of mine with Passkey had problems with a Grnad AM like this, real PITA.