FixVault

DTC P2404: EVAP System Leak Detection Pump Control Circuit Low

WARNING: This page is about a different car, the 2004 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: DTC P2404 Detection Condition & Possible Causes Chart
G01345476Courtesy of MAZDA MOTORS CORP.

Diagnostic Procedure 

Fig 2: DTC P2404 Diagnostic Procedure Chart (Step 1-3)
G01345477Courtesy of MAZDA MOTORS CORP.
Fig 3: DTC P2404 Diagnostic Procedure Chart (Step 4-6)
G01345478Courtesy of MAZDA MOTORS CORP.