Car Alarms: Gargoyle Alarm 2 button., valet mode, exact system

Question
I have the alarm on my 97 blazer.. it was instaled in 98.. The alarm workd great goes off when doors are tying to opened and arms fine. but just recently when i try to arm it, it does not make the duit duit sound, Why could this be?  And do you now where i can get a manual of this alarm from?? Thank you

Answer
After doing a web search it appears as if the Gargoyle line of alarms was a division of Crimestopper.  It appears as if they are no longer supporting those pieces so finding a manual will be difficult at best.  You could give them a call at 800.998.6880 and see if they would be willing to send you a manual.

To the problem you are having, since I am not familiar with that exact system I will offer some general suggestions.  If your LED is lit solid and not blinking, you probably have the system in valet mode.  Valet mode is a feature that allows the convenience features to function (door locks) but disables the security features of a system.  Typically to put a system into and out of valet mode you would have to have the vehicle ignition on and then flip/push a small switch typically located on the driver's side of the vehicle.  Some systems also offer the ability to activate valet mode via the remote, the DEI systems I am familiar with require a door to be open then pressing lock/unlock/lock on the remote.