DTC P0446: EVAP System Vent Control Circuit Problem

Fig 1: DTC P0446 Detection Condition & Possible Causes Chart

Courtesy of MAZDA MOTORS CORP.

Diagnostic Procedure 

Fig 2: DTC P0446 Diagnostic Procedure Chart (Step 1-2)

Courtesy of MAZDA MOTORS CORP.

Fig 3: DTC P0446 Diagnostic Procedure Chart (Step 3-8)

Courtesy of MAZDA MOTORS CORP.