Hello Guys,
When I bought mine, 2007 D40, its DPF was already removed (the inner filters and the mesh/honeycomb) where as all rest of the sensors were intact into the original mountings.. It worked with no codes till a mo month back when suddenly one day the DPF light appeared and it started giving black smoke upon sudden acceleration though was still not in the limp mode..
What I did was un-mount the two pressure sensors pipes/hosings from the DPF and connected them directly through a small piece of metal pipe, which did the trick and DPF light vanished along with the black smoke..
This simulated to the pressure sensors that pressure differenc is with in range and DPF is clean enough.. So not need to put a new DPF..!