Air Injection pump comes on when engine hot
 

My secondary air pump on my 1995 white c220 comes on when the engine is hot sometimes it is only supposed to come on when the engine is cold. This is causing the computer to throw a p0411 code, my question is what causes the air pump to come on electrically, does it get its engine temp information from the coolant temperature sensor.. Any help would be appriciated.

It comes on at times when warm to test the secondary air system. This is normal. When on, the front Oxygen sensor has to drop to or below 40mv in 60 seconds.

I changed my front oxygen sensor and I am still getting code P0411, pump and vacuum valve are working fine any ideas on why I am still getting this code??? Car passed smog, it is just annoying having to reset the light all the time