P0411 Secondary air injection system incorrect flow detected
Checking the 02 sensor VW wants you to check the heater for ground and power as for checking the 02 you would measure the OHM of the 02 sensor. plus if the airinjection system is on the engine management is in a open loop. It is the MAF that measure the flow for the secondary air, the 02 sensor is ignored at this time.
Many times a P0411 for a VW occurs when the secondary air hose comes out