SanDust said:Off the top of my head I'd say chirping and power lights flashing or even lights flashing if it's plugged in and turned on, unless someone is sitting in the front seat or the driver's door is open. (There has to be a sensor for the front seat, yes?).
Something like this.
The car actually dings at you (three times in rapid succession) if you walk away from it with the proximity key while it's on.