Final Stage Unit / Final Stage Resistor

What does the Final Stage Unit or Final Stage Resistor Do? Is there only one function?

I found conflicting evidences here regarding the true function of the FSR. One thread states that it is only linked to the Blower and regulates the blower speed. Surely it has to have more function than that. For those who have good knowledge on this pls shed light. I also noticed that people who have defective FSR have different symptoms, how is that? Im a newbie to this forum. Thanks in Advance.

http://www.xoutpost.com/articles/x5/...nt-bmw-x5.html

Try reading this post.

That's what I noticed different symptoms same answer, so I changed mine, someone was quick to give a solution without really hearing the problem.

You fellas may find this useful:

http://www.motormec.co.uk/aircon.pdf

So essentially it provides a constant resistance to regulate the fan speed, and i guess as its failing the resistance it provides varies (hence fluctuating fan speed), but gradually drops with time.