Javier: Light bulbs are fine (BMW supplied so wattage s/b OK). The PO had had BMW replace the rear harness under warranty as I understand. Doesnt mean a fault hasnt reappeared of course & would agree harness a likely cause. However the Check Control error message varies as to the time it appears. Sometimes as soon as lights are switched on (esp with this 'new' CCM); sometimes only after a while. So It might I think also be an LKM imperfection