i have a 1994 c-280 (w202) and i found that the secondary air pump fuse was blown (maxi fuse 40 a). what does the secondary air pump do? and does it have anything to do with my AC unit.

The Secondary Air Pump is a Aux Air Injection...its Shorted Causing the fuse to Blow Inspect all the Connections.
It Should Have a Check Engine Lite with stored code
Im Not Sure If Its On The Same Circuit as the A/C Blower