Can head AIR passages on a M104 be cleaned without removing the head?

Got this error code today on the 97 C280 M104 inline 6 , 161 K miles

P0410 Secondary Air Injection System Malfunction
Doing a search, the computer is looking for a drop in O2 sensor voltage within 60 sec of the air pump turning on. The pump runs about the same times as my 97 SL320 M104

I still need to check the inlet screen on the pump, test solenoid / diverter valve / vac hoses.