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HOMESERVICE MANUALSFORD2004FOCUS ZX3, 2.0 3, STANDARDREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCETESTING & DIAGNOSISENGINE CONTROLS - POWERTRAIN DTC CHARTS & DESCRIPTIONS - CNG, FLEX-FUEL & GASOLINEDIAGNOSTIC TROUBLE CODE (DTC) CHARTSP2257 - SECONDARY AIR INJECTION SYSTEM MONITOR CIRCUIT LOW
2004 Ford Focus ZX3, 2.0 3, Standard

P2257 - Secondary Air Injection System Monitor Circuit Low

2004 Ford Focus ZX3, 2.0 3, StandardSECTION P2257 - Secondary Air Injection System Monitor Circuit Low
P2257 - SECONDARY AIR INJECTION SYSTEM MONITOR CIRCUIT LOW

Description:  The secondary air injection system monitor circuit is low, indicating the electrical AIR pump is off although the electrical AIR pump was commanded on by the PCM.
Possible Causes: 
  • Open B+ circuit.
  • Open VPWR circuit.
  • Open power circuit between the AIR relay and the AIR pump.
  • Faulted AIR relay.
  • Damaged PCM.
Diagnostic Aids: 
  • The AIR monitor circuit PCM input contains a pull up voltage through a resistance internal to the PCM. This voltage is normally held low by the resistance path through the AIR pump when the pump is off. A single electrical open circuit component such as an AIR relay coil in this multi-component circuit will not be detected by the PCM output driver, yet it will create DTC P2257.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to HM: Secondary Air Injection (AIR) System STEP 37
RENDER: 1.0x

NO RELATED

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