Circuit/System Testing
P0443
- Ignition OFF, disconnect the harness connector at the EVAP canister purge solenoid valve.
- Ignition ON, verify that a test lamp illuminates between the voltage supply circuit terminal A and ground.
- If the test lamp does not illuminate, test the voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the voltage supply circuit fuse is open, test or replace the EVAP canister purge solenoid.
- Connect a test lamp between the voltage supply circuit terminal A and the control circuit terminal B.
- Command the solenoid to 50 percent with a scan tool. The test lamp should flash or illuminate when commanded to 50 percent and turn OFF when commanded to 0 percent.
- If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the control module.
- If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the control module.
- If all circuits test normal, replace the EVAP canister purge solenoid valve.
P0449
- Ignition OFF, disconnect the harness connector at the EVAP canister vent solenoid valve.
- Ignition ON, verify that a test lamp illuminates between the voltage supply circuit terminal A and ground.
- If the test lamp does not illuminate, test the voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the voltage supply circuit fuse is open, test or replace the EVAP canister vent solenoid.
- Connect a test lamp between the voltage supply circuit terminal A and the control circuit terminal B.
- Command the solenoid ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between states.
- If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the control module.
- If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the control module.
- If all circuits test normal, replace the EVAP canister vent solenoid valve.