I have a WW2.0 that starts putting presoak on the vehicle, but before it even gets to the front wheel it stops, goes home, and tells the customer to exit (scolling sign & buzzer). The control panel has an error message that says: no motion detected Check for obstruction on gantry track. The prox switches all seem to be working fine. It has done this erratically over the past couple of weeks, but now does it every car, so I had to shut it down. Any suggestions about what to look for? Could a bad eye be causing this?