DTC P0446: Evaporative Emission System Vent Control Circuit

2010 Ford Focus S, StandardSECTION DTC P0446: Evaporative Emission System Vent Control Circuit
DTC P0446: EVAPORATIVE EMISSION SYSTEM VENT CONTROL CIRCUIT

Description:  Monitors the canister vent (CV) solenoid circuit for an electrical failure. The test fails when the signal moves outside the minimum or maximum allowable calibrated parameters for a specified canister vent duty cycle by powertrain control module (PCM) command.
Possible Causes: 
  • VPWR circuit open
  • KAPWR circuit open (vehicles equipped with engine off natural vacuum (EONV) EVAP leak check monitor)
  • CV solenoid circuit short to ground
  • Damaged CV solenoid
  • CV solenoid circuit open
  • CV solenoid circuit short to voltage
  • CV solenoid circuit short to KAPWR (vehicles equipped with engine off natural vacuum (EONV) EVAP leak check monitor)
  • Damaged PCM
Diagnostic Aids:  To verify normal functioning, monitor the EVAP canister vent solenoid signal PID EVAPCV and the signal voltage (PCM control side). With the valve open, EVAPCV indicates 0% duty cycle and a voltage approximately equal to battery voltage. When the valve is commanded fully closed, EVAPCV indicates 100% duty cycle, and a minimum voltage drop of 4 volts is normal. Output test mode (OTM) may be used to switch output on/off to verify function.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST HX .
RENDER: 1.0x

NO RELATED

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