Clifford has this feature on their alarms as an anti-carjacking feature. I have it.

Heres how it works:

Every time you start the car, you must enter your binary code on the 2 button switch. if the code is not entered after startup, or after any door has been opened with the engine running, the carjacking feature will activate.

Heres what it does:

The first time the brake pedal is pressed, the alarm light will start flashing, the alarm will chime with the flashes. This goes on for 30 seconds. After 30 seconds, if the code is not entered, the alarm will kill the ignition the first time the RPM's fall below 2,000. The siren will now sound full, and CAN NOT be deactivated with the remote, only with correct code on binary switch.

So, if someone takes your truck, they get a few blocks at most, and it stalls in a more visable place than where it was parked.

You do have to hit the code anytime you let someone out with the engine running, but doing it becomes routine after a short while.

John C.