Steve2469

Hi All I am in the process of trying to fix my parking sensors on a 2007 1.8 tdi Galaxy and there are a few things I am trying to find out if anyone out there can help. Both my front and rear sensors dont work, had it on a ford diagnostic system and it tells me front left two are out and rear right two are also not working. I removed the working ones from the front and fitted them in the rear to replace the broken ones there. The rear still do not work! 1 should the rear sensors work if one of the front ones is broken? 2 do these sensors make a clicking sound like earlier models ? ( I dont hear clicking coming from any of them ) 3 does anyone know if the sensors can be checked out using a volt/ohm meter 4 does anyone know where I can buy a cheaper alternative to ford sensors Any help at all would be appreciated Steve