DTC Confirmation Test

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

NOTE: Before performing test, ensure fuel tank is 1/4-3/4 full, vehicle is parked on a level surface and ambient temperature is 32-86°F (0-30°C).

Malfunction is detected when EVAP control system has a leak or does not operate properly. Possible causes are:

Incorrect fuel tank vacuum relief valve.
Incorrect fuel filler cap.
Fuel filler cap open or leaking.
Foreign matter in fuel filler cap.
Leak in hose between intake manifold and EVAP Canister Purge Volume Control Valve (EVAP-CPVCV).
Foreign matter in EVAP Canister Vent Control Valve (EVAP-CVCV).
Leak in EVAP canister or fuel tank.
Leak or blockage in EVAP purge line.
Leak or blockage in hose to EVAP Control System Pressure Sensor (EVAP-CSPS).
Defective EVAP-CVCV or circuit.
Defective EVAP-CPVCV or circuit.
Defective Absolute Pressure (AP) sensor.
Defective Fuel Tank Temperature (FTT) sensor.
Defective MAP/BARO solenoid or circuit.
Blockage in MAP/BARO solenoid hoses.
Leak between EVAP canister and EVAP-CVCV.
Defective water separator.
EVAP canister saturated with water.
Defective EVAP-CSPS.
Defective fuel level sensor or circuit.

To set DTC, drive vehicle according to specified driving pattern to set System Readiness Test (SRT) codes. See SYSTEM READINESS TEST under SELF-DIAGNOSTIC SYSTEM. Stop vehicle and go to next step.
Using scan tool, check SRT status of EVAP system. If EVAP system SRT is complete, system is okay at this time. If EVAP system SRT is incomplete, turn ignition off, wait at least 10 seconds and go to next step.
NOTE: It is not necessary to allow engine to cool before driving vehicle.
Perform driving pattern again. Using scan tool, retrieve DTCs. If DTC P0440, DTC P1440 or DTC P1447 is set, perform appropriate diagnostic procedure. If DTC P0440, DTC P1440 or DTC P1447 is not set, go back to step 2.