Perform the Diagnostic System Check - Engine Controls prior to using this diagnostic procedure.

The evaporative emission (EVAP) canister purge valve is used to purge fuel vapor from the EVAP canister to the intake manifold. The EVAP canister purge valve is pulse width modulated (PWM). Ignition voltage is supplied directly to the EVAP canister purge valve. The engine control module (ECM) controls the solenoid by grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to a voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage.

DTC P0444, is a Type B DTCs.

DTC P0444, is a Type B DTCs.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

1. Engine idling, observe the DTC information with a scan tool. DTC P0444 should not set.
2. If the vehicle passes the Circuit/System Verification test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

1. Ignition OFF, disconnect the harness connector of the EVAP purge solenoid.
2. Ignition ON, verify that a test lamp illuminates between the ignition 1 voltage circuit and ground.

⇒	If the test lamp does not illuminate, test the ignition 1 voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition 1 circuit fuse is open, test all components connected to the ignition 1 voltage circuit and replace as necessary.

3. Test for 3.0-4.5  volts between the control circuit and ground.

⇒	If less than 3.0 volts, test the control circuit for a short to ground or open/high resistance. If the circuit/connections test normal, replace the ECM.

⇒	If greater than 4.5 volts, test the control circuit for a short to voltage. If the circuit/connections test normal, replace the ECM.

4. Ignition OFF, connect a 5-amp fused jumper wire to one terminal of the solenoid and B+.

Important: Listen for an audible sound or feel the solenoid body to determine if the solenoid activates.

5. Connect a jumper wire to the other terminal of the solenoid and ground. The solenoid should turn ON.

⇒	If the solenoid remains OFF, replace the solenoid.

6. If all circuits/connections test normal, replace the ECM.

1. Measure for 24-28 ohms of resistance between the terminals of the EVAP purge solenoid.

⇒	If the resistance is not within the specified range, replace the EVAP purge solenoid.

2. Test for infinite resistance between each terminal of the EVAP purge solenoid and the EVAP purge solenoid housing.

⇒	If less than infinite resistance, replace the EVAP purge solenoid.