Some security systems have pannic alarm while the ignition is on. Most DEI subsidiaries have this. Code Alarm does not. Thier pannic is only operative with the ignition off. This is an inherent aspect of the system control, and cannot be bypassed. You can, however, add a second control box to a separate siren..... but that's alot of work for such a small feature. My suggestion is to get a DEI product if you MUST have that feature.