P0446

DTC P0446
Purge cannister vent valve functionality fault Drive cycle C:Signal out of range - below minimum.

Possible causes by suggested order of priority:
- Cannister vent seal valve fault - stuck closed or blocked.
- purge cannister blocked.
- Cannister purge valve fault - sticking open.
- Fuel tank pressure sensor fault - inaccurate.

Cannister vent seal valve fault - stuck closed or blocked.
CHECK THE FOLLOWING
- Disconnect vent seal valve from purge can, Attempt to blow through vent seal valve.
- Visual check of vent seal valve, check for blockage and charcoal contamination.
POSSIBLE FAULTS
- Faulty vent seal valve.
- Vent seal valve blocked with charcoal from cannister.

purge cannister blocked.
CHECK THE FOLLOWING:
- Purge can not blocked.
- Visual check of purge can - charcoal not broken up (contamination in purge or vent valve).
POSSIBLE FAULTS
- Faulty purge can.

Cannister purge valve fault - sticking open.
CHECK THE FOLLOWING:
- Disconnect purge valve. Attempt to suck air through closed valve using suitable tool.
- Visual check of purge valve - check for charcoal contamination.
POSSIBLE FAULTS
- Faulty purge valve.
- Purge valve jammed open with charcoal from purge can.

Fuel tank pressure sensor fault - inaccurate.
CHECK THE FOLLOWING:
- Pressure sensor reads close to zero with filler cap removed.
- If equipment available pressurize the tank and check that the reading on the sensor is accurate.
POSSIBLE FAULTS
- Faulty fuel tank pressure sensor.