Just bought new Sportage First Edition and had tow bar fitted by supplier. Tried trailer on car and whenindicatorsswitched on, the trailer and car indicators flashed once thenALL went off. Unplugged trailer and car indicators worked ok. Seems now that there should be an "extra" box of tricks in the flasher cricuit which is to cost £160 (don't know if this includes fitting). Anyone know any more about this?