I have a 2010 S Convertible that has had it's auxiliary water pump replaced per the recall. In the last two weeks, I've noticed just the electric motor for that auxiliary pump running after the engine is off. The fan doesn't run, just the motor--sounds like sizzling and it can run for 10 to 15 minutes--it can be associated with a burning rubber smell.I know the fan can run after the engine shuts off to cool the turbo but I've never had the electric motor by itself run. The mechanic said as best he can tell the fan is working properly (comes on when AC is on) and the engine isn't over heating.

I would prefer not to replace this if I don't need to, i.e. would like to wait until it fails but the burning smell has me worried. Also the mechanic hadn't worked on a lot of mini's so he may not necessarily realize if this is a sign of impending doom.

Advice?