DTC 0801

COMPONENT DESCRIPTION
The vacuum cut valve and vacuum cut valve bypass valve are installed in parallel on the EVAP purge line between the fuel tank and the EVAP canister.
The vacuum cut valve prevents the intake manifold vacuum from being applied to the fuel tank.
The vacuum cut valve bypass valve is a solenoid type valve and generally remains closed. It opens only for on board diagnosis. The vacuum cut valve bypass valve responds to signals from the ECM. When the ECM sends an ON (ground) signal, the valve is opened. The vacuum cut valve is then bypassed to apply intake manifold vacuum to the fuel tank.




EVAPORATIVE EMISSION SYSTEM DIAGRAM




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




ECM TERMINALS AND REFERENCE VALUE
Specification data are reference values and are measured between each terminal and (25) (ECM ground).




ON BOARD DIAGNOSIS LOGIC




DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE

NOTE: If "DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 seconds before conducting the next test.

TESTING CONDITION: Before performing the following procedure, confirm that battery voltage is more than 11 V at idle.

With Consult
1. Turn ignition switch "ON".
2. Select "DATA MONITOR" mode with CONSULT.
3. Start engine and wait at least 5 seconds.
4. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".

OR

With Generic Scan Tools
1. Start engine and wait at least 5 seconds.
2. Select "MODE 7" with GST.
3. It 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".

OR

Without Scan Tools
1. Start engine and wait at least 5 seconds.
2. Turn ignition switch "OFF", wait at least 10 seconds and then turn "ON".
3. Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.
4. If 1st trip DTC is detected, go to "DIAGNOSTIC PROCEDURE".







WIRING DIAGRAM




DIAGNOSTIC PROCEDURE

COMPONENT INSPECTION

Vacuum cut valve bypass valve
Check air passage continuity.







With Consult
Perform "VC/V BYPASS/V" in "ACTIVE TEST" mode.

OR







Without Consult
If NG or operation takes more than 1 second, replace vacuum cut valve bypass valve.