Hey Cooper-ites,
I own a 2002 Cooper S with 185,000 miles on it. It has been, overall, very reliable. I have recently suffered loss of power steering function once the vehicle gets warm. The power steering works fine until it gets hot and then it stops working until I shut down the engine long enough for it to cool. The power steering pump cooling fan functions only when the radiator fan kicks on. I think it should run all the time the engine is running.
At over $500.00 for a replacement pump, I'd like to find out if there is some electrical issue or wiring path problems that MIGHT cause this HEAT RELATED temporary failure. I've read where many pumps have failed all together but I haven't heard of this intermittent problem. Any input would be appreciated.

 

There are threads on this problem. Regarding the intermittent operation, it was reported that when the PS pump overheats it has some protection mode. Regarding the PS fan, it depends on when your 2002 was made. Up until Dec 2002 the PS fan comes on only with the high-speed engine cooling fan. After that it comes on with the low-speed engine cooling fan.

 

Yep, and those same threads will reveal that you've probably achieved at least two times the sort of life expectancy most get out of their EHPS pump. Congrats!

Thing is, since the electrical side of the unit is self-contained, as the brushes naturally wear there is nowhere for the highly corrosive and conductive brush dust to go -- except into the windings and even the internal controller card, causing all sorts of strange behavior.

If your unit is the original and it's never had any preventive maintenance I'm willing to bet it's on borrowed time. Options are: (1) remove it, clean out the motor, and replace it, which might extend its life a bit more (some good DIYs on this procedure); or (2) bite the bullet and replace the unit altogether (also can be done as a DIY). The spontaneous fires thread would be enough to convince me not to mess around and to go ahead with Option #2.

 

Congrats on the long pump life...
The fan is working as it should...
As previously said, the pump, since it is an electric motor with brushes, is a bit if a wear item, just like an alternator....it wears....and needs to be rebuilt/replaced. Since the hydrolic side or the electronics are likely beyond their expected life, imo a new pump would be the most prudent option.