Hi I've had my new (1999) silverado for 1 week and 2day she wouldn't start! Truck is like new inside and out and runs like it's new...60K mi. Sometimes the security light stays on while driving and the manual says that could be a problem with the passlock system? The truck always starts the instant you turn the key but 2day while out running errands she wouldn't start? She tried to start but it seemed that something electrical was shutting it down before it could keep running? I tried several times and same result. I waited about 20 min and tried again and it started right up? Any help will be greatly appreciated!