Possible Causes

WARNING: This page is about a different car, the 2002 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.

Malfunction is detected when an excessively high voltage is sent to ECM from EVAP-CSPS. Possible causes are:

EVAP-CSPS circuit open or shorted.
Defective EVAP-CSPS.
Defective EVAP Canister Vent Control Valve (EVAP-CVCV).
Defective EVAP canister
Defective water separator.
Defective hose between EVAP-CVCV and water separator.

NOTE: Before proceeding, ensure ambient temperature is more than 41°F (5°C).