Hi. I asked this question on the Mini2 forum, but I thought maybe somebody here might be able to lend some of their experience to the problem.

A friend of mine has a 2005 Mini Cooper S and the power steering pump runs with the engine off and the key out. I've checked it up on the jack and the fan is definitely not running, so it's just the pump.

My question is, does anybody know what causes these to fail? I've seen a few other people that have had this problem and everybody seems to say that the pump needs to be replaced, but that would only make sense if the pump is internally modulated. If it's not internally modulated, then the problem would have to be either a relay, a power steering control module or another module controlling it.

Unfortunately, I can't access the connector with the Mini up on that little jack and I won't be able to put it up on a lift until next week, so does anybody know how these EHPS pumps are controlled?

Thanks

 

This thread might help, I think it confirms the electronic controls are internal.
https://www.northamericanmotoring.co...=%28brushes%29

 

Thanks a lot, Mab! You're right, MikeL said:

"...there is an electronic circuit inside the motor housing that also has the potential for failure. It is conformal coated which should keep brush dust and moisture out of the electronics but I wonder if some of the problems have been due to conformal coating being too thin."

And they went on to discuss it in a little more detail. Thanks for the info. Now it definitely makes sense that the pump could be the problem, unless there's also an external control unit that is sending a false signal (which I'd have no way to test anyway). Of course, I probably would have seen something about that on the forums by now.

I'm wondering now if maybe my friend might want to keep the old unit instead of sending back the core for $50. You never know...if the new one fails mechanically, we might be able to switch the electronics/module over and reman the original.

Thanks again.