The door open warning light on the dash of my new Doblo keeps flashing. I reclose all the doors and tailgate and the problem seems to be resolved, but then within a few miles the darn things starts flashing again. Most of the time it flashes when I'm turning (left or right) or when accelarating from stationery. I'm positive all the doors and tailgate are firmly close and its really starting to irritate me. Any ideas anyone?