went to the dealer today for parts and the defender (300tdi) ran perfectly as always, i fitted the new antenna and everything was going good until my dad tried to move it again, the engine started fine with the usual ploom of black smoke but when he put it in first gear the diff lock light was on so he moved the low ratio stick to the neutral position but the 110 just wouldn't move, anyone know what the problem might be, help would be very much appreciated?, thanks Rob