Code Definition
- DTC P0447: EVAP Emission Control System Vent Circuit Open
- DTC P0448: EVAP Emission Control System Vent Circuit Shorted
Note. Before performing any diagnostic test, refer toWARNINGS, CAUTIONS and NOTES in DIAGNOSTIC TESTS .
Note. Testing individual components does not isolate shorts or opens. Perform all voltage tests using a Digital Volt-Ohmmeter Meter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use ohmmeter to isolate wiring harness shorts or opens.
Diagnostic Aids
Malfunction code is set when solenoid coil surge voltage (system voltage +2) is not detected when EVAP emission vent solenoid is turned on/off. Check for following possible problems
- Open or short between Canister Control Valve (CCV) and Main relay.
- Open or short between CCV and ECM.
- Faulty CCV.