I just figured this out in about 30 minutes.
PLease read thru the whole instructions before you attempt this fix. down towards the bottom regarding the spring in the Auto Power Cord Reel Assembly
If you are good at taking things apart & putting them back together, you can get into the retractable cord unit, being very careful as not to break any of the plastic parts inside as you remove the main top cover (from the handle) and disconnect it (plastic hinge - blue tabs next to the black plastic insert guides). After you remove the cover, remove the filter & then the two silver screws by the by the filter - they are visible. Those two screws hold down the Black actuators (on & off and power cord Auto Power Cord Reel Assembly and speed control Unit) That should lift straight up - disconnecting it from the seat. Unscrew all 5 black screws that holds down the housing for the motor & retractor unit. Inside, there is one silver screw holding down the retractor unit and that will lift straight up. Disconnect the retractor spring (making certain that you note how it is connected!!! Remove the white plastic reel holding the power cord and clean the 4 contacts and the area where it contacts the circular stationary parts. It is probably oxidized from all the yanking. before you put it back together, lift the contact prongs a bit so that it will make a better connection. You may need to put a few washers on the black shaft on the motor side to push the white plastic reel towards the retracting spring side. That will help make a better contact. The trickiest part is reconnecting the spring back onto the white plastic reel. You should get it after a few tries. Put it all back together and it should give you a few more years before it goes on the blink again. By the way, fully extend the cord before you turn on the Vac, & turn it off before you retract the cord so that you do not cause the contacts to spark, it should last a lot longer.
You can purchase the Auto Power Cord Reel Assembly for $139 from
http://www.sweetsweep.com/micapocoreas.html
I didn't do any research regarding finding the cheapest price for this unit but it is the exact same one in the Meile S3141.
Good luck!
Let me know how you do!
Mark from Chinatown NYC, June 2010