Kitulu

I recently purchased a 2008 Grand Voyager CRD with 300K on the odometer. I realize that it takes a diesel engine a long time to heat up, but it seems to take longer than it should. For example, it takes me 10-15 minutes to drive to work. The last few days it has been around 2-4 degrees C in the morning. The heater barely begins to blow lukewarm air in that time, and the temp gauge moves just above the lowest mark. I have been reading about the aux heater. I see the light on the dash come on with the rest of the dash lights when I first start the van, but it then turns off and never comes back on. When I park the van and turn off the engine, I can hear the vent working, and see the exhaust smoke if it is cold enough. How can I tell if the aux heater is actually working? Is the overall behavior normal?