P0411: Secondary Air Injection (Air) System Upstream Flow

2004 Ford Focus ZX3, 2.0 3, StandardSECTION P0411: Secondary Air Injection (Air) System Upstream Flow
P0411 - SECONDARY AIR INJECTION (AIR) SYSTEM UPSTREAM FLOW

Description:  The secondary air injection system does not detect the presence of air in the exhaust when introduced by the secondary air injection system.
Possible Causes: 
  • AIR bypass solenoid circuit open.
  • AIR bypass solenoid leaking/blocked or stuck open/closed.
  • Electric AIR pump - no/low air flow.
  • AIR diverter valve leaking/blocked or stuck open/closed.
  • AIR 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 HO2S lean. A single electrical circuit open, such as an AIR bypass solenoid, in this multi-component circuit will not be detected by a PCM output driver circuit, yet it will create DTC P0411.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All - GO to PINPOINT TEST HM: SECONDARY AIR INJECTION (AIR) SYSTEM Step 17. GO to PINPOINT TEST HM: SECONDARY AIR INJECTION (AIR) SYSTEM Step 17.
RENDER: 1.0x

NO RELATED

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