Dubdriver, did you get this problem resolved? I have a similar problem which is driving me insane and I could do with the some help from you experts! When selecting reverse, I get either a constant tone or a beeping as if I were approaching an object. This is intermittent but happens more often than not. I have plugged in a restricted version of VAG COM and this indicates that the O/S/F middle sensor next to the number plate is detecting an object as the distance measured is much less than the other sensors. I have swapped the sensors around but the fault still lies with the same sensor. This then led me on to check the wiring loom. With the aid of a wiring diagram, I removed the bumper trim and all the front sensors and removed the wiring loom between the sensors and the connector behind the N/S/F fog light. This was inspected and continuity tested to check for any breaks but all seems OK and all the plugs look clean. I replaced the front loom and tested the whole circuit again between the (disconnected) control unit connectors under the passenger seat and the sensor connectors at the front using both a continuity tester and a megger type insulation tester. All tested out fine. I reconnected the sensors and the control unit but the fault is still there. This lead me to believe that the fault must lie with the control unit as I had tested and eliminated the sensors and the wiring. So I bought a new control unit from VAG parts at a cost of around 80 quid. I plugged it in and guess what? The fault is still there. I am now at a loss as to what else it could be. Having come this far, I really don't want to admit defeat and hand it over to a dealer. Any ideas anyone?