I have a Vauxhall Omege 2.6 saloon with a blower fault,
I have removed the fan but found that it is working, I have now come to the conclussion that it may be the resistor pack (I hope) the thing I cant see is how do you get the resistor out? I also have no idea what else the problem could be, I have been looking for the relay for the unit but dont seem able to find it,

Francis, November 2008

If your fan is only working on the fourth speed then it's the heater blower resistor. Usually located behind glove box on most cars. Normally looks like a plastic disc, with a resistor on it. The last one I changed was on a Laguna, think I turned it & then came straight off.
If you had a test meter you could test supply to heater blower motor, then to resistor

George., November 2008