Not only u need to turn it off, you had to plug it off and hide it quickly as well, and dun let your ciggy lighter left open coz that will raise suspicion... any how after u've done all that, if they suspect you they can always search the car and find it, then you'll have to pay the hefty fine.
Speaking of ciggy lighter, my one is missing, which is not good actually. Not that I smoke, but I just dun feel like leaving my car ciggy lighter plug with nothing in it. Looks dodgy like having a radar detector somewhere in the car. I can't seem to find any replacement in K-Mart Auto/Repco... Guess have to go to nissan dealer n order one from them?