Thank you for the reply as I said I am totally bewildered by electronics so well beyond my knowledge I'm happy to pay someone to do this if possible, we will be having a switch inside the truck cab to turn this on/off but it's just the sensor kit side of things I'm struggling with

Hi all I wonder if you guys can help me and point me in the right direction, we are after a 12V ultrasonic sensor that is waterproof to put on the back of a truck, when a solid item gets within the sensors range we want it to trigger a Light/LED preferably from Green - Yellow then red depending on t...