P2258 - Secondary Air Injection System Monitor Circuit High

2004 Ford Focus ZX3, 2.0 3, StandardSECTION P2258 - Secondary Air Injection System Monitor Circuit High
P2258 - SECONDARY AIR INJECTION SYSTEM MONITOR CIRCUIT HIGH

Description:  The secondary air injection system monitor circuit is high, indicating the electrical AIR pump is on although the electrical AIR pump was commanded off by the PCM.
Possible Causes: 
  • AIR relay fault - stuck closed.
  • AIR pump fault - circuit open in motor.
  • Open ground to AIR pump.
  • Open AIR monitor circuit between the AIR pump and the PCM.
  • Short to power in the AIR relay to AIR pump power circuit.
  • 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.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to HM: Secondary Air Injection (AIR) System STEP 49
RENDER: 1.0x

NO RELATED

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