diagnostic codes

my buddy’s check engine light will not turn off in he vw passat. he has been driving it for a while now and its running absolutely fine! i found places on the net i can find the code and what the code means…this is what it says it means
Secondary Air Injection System Incorrect Flow
BUT whats that mean? anyone know where i can find the meanings for these codes?

thanks alot

The secondary air injection is the system that injects air in to the exhaust manifolds when the engine is cold in order to help burning not burned gas to reduce emissions and warm catalitic converters sooner to get them work faster.

so what needs to be done to fix the problem?

its bad and needs replaced? :dunno: