When you engage into "R" gear, there are beep sounds for 2
secs.. Then it will go away. It will only come back with increasing
frequency (or non stop mode) when it senses a close (very near)
object or something... other than that, it will not beep anymore..
at least this is how my car sensor react. Maybe you could ask a
technician to check if your sensor could be set in such a
way...
In conclusion, i find this sensor very useful during reversing
