DTC P0443
- Evaporative Emission (EVAP) Purge Solenoid Control Circuit
DTC P0449
- Evaporative Emission (EVAP) Vent Solenoid Control Circuit
Diagnostic Fault Information
Circuit/System Description
An ignition voltage is supplied directly to the evaporative emission (EVAP) canister purge solenoid valve. The engine control module (ECM)
grounds the EVAP canister purge solenoid valve control circuit through an internal switch called a driver. The ECM monitors the status of the
driver. The EVAP canister purge solenoid valve is pulse width modulated (PWM). A scan tool will display the amount of ON time as a percentage.
Battery voltage is supplied to the EVAP canister solenoid valve. The ECM grounds the EVAP canister vent solenoid valve control circuit through
an internal switch called a driver. The ECM monitors the status of the driver. A scan tool will display the commanded state of the EVAP canister
vent solenoid valve as ON or OFF.
Conditions for Running the DTC
* The ignition is ON.
* The system voltage is between 9-18 volts.
* DTCs P0443 and P0449 run continuously when the above conditions are met.
Conditions for Setting the DTC
The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for a minimum of 5 seconds.
Action Taken When the DTC Sets
DTCs P0443 and P0449 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P0443 and P0449 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Description and Operation
Evaporative Emission Control System Description (See: Powertrain Management/Computers and Control Systems/Description and
Operation/Evaporative Emission Control System Description)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Troubleshooting with a Test Lamp (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Circuit Testing/Troubleshooting with a Test Lamp)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
