P0446 Evaporative Emission System Vent Control Circuit
To judge if there is open circuit in the evaporative emission ventilation solenoid drive circuit, PCM measures the surge voltage of the evaporative emission ventilation solenoid coil.
The PCM drives the evaporative emission ventilation solenoid. After the solenoid is turned off, the PCM will check if the solenoid coil produces a surge voltage of 2 V or more.
Check Conditions
Engine is being cranked.
Battery positive voltage is at between 10 and 16 volts.
Judgment Criteria
The evaporative emission ventilation solenoid coil surge voltage (battery positive voltage + 2 volts) is not detected for 0.2 second.
The PCM monitors for this condition once during the drive cycle.
Check Conditions
Battery positive voltage is at between 10 and 16 volts.
ON duty cycle of the evaporative emission purge solenoid is 0 percent.
Evaporative emission ventilation solenoid is ON.
More than 1 second has elapsed after the above mentioned conditions have been met.
Judgment Criteria
The evaporative emission ventilation solenoid coil surge voltage (battery positive voltage + 2 volts) is not detected for 1 second. When the evaporative emission ventilation solenoid is turned OFF.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are: )
- Evaporative emission ventilation solenoid failed.
- Open or shorted evaporative emission ventilation solenoid circuit, or loose connector.
- PCM failed.
To judge if there is open circuit in the evaporative emission ventilation solenoid drive circuit, PCM measures the surge voltage of the evaporative emission ventilation solenoid coil.
The PCM drives the evaporative emission ventilation solenoid. After the solenoid is turned off, the PCM will check if the solenoid coil produces a surge voltage of 2 V or more.
Check Conditions
Engine is being cranked.
Battery positive voltage is at between 10 and 16 volts.
Judgment Criteria
The evaporative emission ventilation solenoid coil surge voltage (battery positive voltage + 2 volts) is not detected for 0.2 second.
The PCM monitors for this condition once during the drive cycle.
Check Conditions
Battery positive voltage is at between 10 and 16 volts.
ON duty cycle of the evaporative emission purge solenoid is 0 percent.
Evaporative emission ventilation solenoid is ON.
More than 1 second has elapsed after the above mentioned conditions have been met.
Judgment Criteria
The evaporative emission ventilation solenoid coil surge voltage (battery positive voltage + 2 volts) is not detected for 1 second. When the evaporative emission ventilation solenoid is turned OFF.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are: )
- Evaporative emission ventilation solenoid failed.
- Open or shorted evaporative emission ventilation solenoid circuit, or loose connector.
- PCM failed.