DTC P0411: Secondary Air Injection (AIR) System - Incorrect Upstream Flow Detected

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P0411 - SECONDARY AIR INJECTION (AIR) SYSTEM - INCORRECT UPSTREAM FLOW DETECTED

Description:	The AIR system does not detect the presence of air in the exhaust when introduced by the AIR system.
Possible Causes:	AIR bypass solenoid circuit open AIR bypass solenoid leaking/blocked or stuck open/closed Electric AIR pump with no or low air flow AIR diverter valve leaking/blocked or stuck open/closed AIR hoses restricted or leaking AIR vacuum hoses restricted or leaking
Diagnostic Aids:	In order to test the AIR pump, it must be capable of driving the heated oxygen sensor (HO2S) lean. A single electrical circuit open, such as an AIR bypass solenoid, in this multi-component circuit will not be detected by a powertrain control module (PCM) output driver circuit, yet it will create DTC P0411.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	-	GO to HM: Secondary Air Injection (AIR) System STEP HM17.	GO to HM: Secondary Air Injection (AIR) System STEP HM17.