Hi all, my second posting on this great forum. Best one I have ever used. Anyway to business. I have a 2.3 Zetec 2002. On selecting the parking sensors I get the long tone then the 'flashing P' symbol indicatinf failure. I have started the engine and the advice of this forum got my 'lug 'ole' around each sensor and found that all the front and rear sensors are 'clicking' (sounds like a small static discharge). I understand the control unit is under the passenger seat as I suspect this might the best itme to check next. Please can someone confirm I am right to go here next as I surprised it could have failed if all the sensors are firing. Am I missing something. There has never been any water ingress in there as far I can see. Lastly, anybody any idea how much they cost? Thanks in advance for any help. Rick