Just purchased a 08 plate Freelander 2 XS - In my wisdom I failed to check some of the basics (yes I know I've done wrong!) and I believe the parking sensors both front and back are not working - I can't hear any beeps etc. I've seen the switch on the dash - do I need to activate this every time I want to use them? Seems a bit strange as I would expect the rear's to kick in when I put it in reverse? Any ideas welcome!

Do you have the original sound system?

Yes original sound system, no modifications have been made to the vehicle from what I can see / tell.

Parking sensors engage every time you select reverse. Button turns them off when full of water
Haven't had any sensors fail,but ........ The front sensors plug into a loom, this loom then plugs into the main loom just in front of the left front wheel. If the plug fills with water it can cause a short that drags the whole system down.

So unplug front loom, and see if rear comes alive, try the same with the rear and see if the front comes alive.
You can get to the front plug without removing the front of the car Tangiers Orange - gone, missing her
Replaced by Ewok what a mistake - now a happy Disco Sport owner

Have alook at this thread
http://www.freel2.com/forum/topic26937.html No Longer the owner of a 2013MY Fuji White GS

"Fiat Lux" a philosophy not a car

Thanks all, As Andy131 has pointed out it seems they have failed since the dash light is flashing orange. I have someone at work has a OBD2 cable and relevant software so will go down that route before disconnecting the looms.

Fingers crossed it's not a costly repair!