Recently I purchased another 2001 XJR. Running A/C, I noticed that even when the fan speed is set to MAX, the vents do not seem to blow all that hard. And, in fact, some air feels like it is coming out of the steering column, that space right underneath where the column meets the dash. I crawled under the passenger side footwell, looked up to have a look and saw this fan. Is that original? It sure looks out of place or doesn't fit right, but looks like it has been there a long time.

 

normal only for "R" cars.
It's the fan to cool the ECM (engine computer)

 

You need to have BOTH climate control fans operating or the flow will feel 'weak'.

bob gauff