JV, I liked the idea of trying a "hard reset" by disconnecting the battery. I tried it yesterday. When reconnected, the DSC, brake and airbag lights were on with key in position 2 and turned off when in position 3. I thought it just may have done the trick, but unfortunately the DSC button still does not seem to do its job, no matter how long I press and hold it.

I may try to pop out the center console and take a look at the button, but I would guess that this is more likely a software issue. Fortunately, I purchased the highest available level of coverage for my aftermarket warrantee (after reading about all of the mysterious "Open the pod bay door, Hal" issues with X5 computers and software)--as long as they consider the DSC a "powertrain control module," I am theoretically covered.

Thanks again everyone!

__________________

'01 X5
'98 M3
'73 /5