Parking Sensor Issue or Parking Sensor Unit

[samastonlongley]

I've found my parking sensors haven't been working since getting my car. When I bourght the car one of the central parking sensors was missing. I bourght a replacement but the parking sensors still beep solid when I switch them on. My other 3 sensors tick when put into reverse, all except the new one. My question is do I have three faulty sensors or an entire parking sensor unit fault? Thanks in advance

[john ryan]

They will tick if working. Suggest you swop over a working one for the replacement to check the wiring/control unit. If the non-ticking unit doesn't tick in the new location, or vice versa, you will have identified the problem.

[samastonlongley]

Thanks for your reply, I did some tests last night, I swoped the non ticking sensor over with the other side and when it's at the one side of of he car it ticks. So if we are saying when they tick they are working I've proved it's not the sensor, could it be the wiring? Seems odd that just one would not work? If it is the parking sensor unit where abouts is it on the car should I need to replace it?

Many thanks