Code 0903

COMPONENT DESCRIPTION

NOTE: If both DTC P0440 and P0446 are displayed, perform TROUBLE DIAGNOSIS FOR P0446 first.

The EVAP canister vent control valve is located on the EVAP canister and is used to seal the canister vent.
This solenoid (the EVAP canister vent control valve) responds to signals from the ECM.
When the ECM sends an ON signal, the coil in the solenoid valve is energized.
A plunger will then move to seal the canister vent. The ability to seal the vent is a necessary part of the diagnosis algorithms for other evaporative loss system components.
This solenoid valve is used only for diagnosis, and usually remains opened.
When the vent is closed, under normal purge conditions, the evaporative loss system is depressurized allowing "EVAP Control System (Small Leak)" diagnosis.





CONSULT REFERENCE VALUE IN DATA MONITOR MODE
- Specification data are reference values.





ECM TERMINALS AND REFERENCE VALUE

Remarks: Specification data are reference values, and are measured between each terminal and (25) (ECCS ground) with a voltmeter.





ON BOARD DIAGNOSIS LOGIC

DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE
Perform "Procedure for malfunction A". If the DTC cannot be confirmed, then perform "Procedure for malfunction B". Procedure for malfunction A

With Consult
(1) Turn ignition switch "ON".
(2) Select "DATA MONITOR" mode with CONSULT
(3) Start engine and wait at least 5 seconds.

OR

With Generic Scan Tool
(1) Start engine and wait at least 5 seconds.
(2) Select "MODE 7" with GST.

OR

Without Scan Tool
(1) Start engine and wait at least 5 seconds.
(2) Turn ignition switch "OFF", wait at least 5 seconds and then turn "ON".
(3) Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.








OVERALL FUNCTION CHECK
This procedure can be used for checking the overall function of the EVAP canister vent control valve circuit. During this check, a DTC might not be confirmed.

Procedure for malfunction B
1. Remove EVAP canister vent control valve from EVAP canister and disconnect hoses from the valve.
2. Check air passage continuity.
If removed, clean valve using air blower. Make sure new 0-ring is installed properly.

EC-VENT/V-01 Evaporative Emission (EVAP) Canister Vent Control Valve (DTC: P0446):

Evaporative Emission (EVAP) Canister Vent Control Valve (DTC: P0446):

DIAGNOSTIC PROCEDURE








COMPONENT INSPECTION

EVAP canister vent control valve
Check air passage continuity.
If NG, clean valve using air blower or replace as necessary.
Make sure new O-ring is installed properly.








EVAP control system pressure sensor
1. Remove EVAP control system pressure sensor from bracket with its harness connector connected.
2. Remove hose from EVAP control system pressure sensor.
3. Apply vacuum and pressure to EVAP control system pressure sensor with pump as shown in figure.
4. Check output voltage between terminal (2) and engine ground.
5. If NG, replace EVAP control system pressure sensor.