P0444

DTC P0444 EVAP. EMISSION SYSTEM-PURGE CTRL VALVE CIRCUIT OPEN




COMPONENT LOCATION

GENERAL DESCRIPTION
The evaporative emission control system prevents hydrocarbon (HC) vapors from the fuel tank from escaping into the atmosphere where they could form photochemical smog. Gasoline vapors are collected in the charcoal canister. The PCM controls the Purge Control Solenoid Valve (PCSV) to purge any collected vapors from the canister back to the engine for combustion. This valve is actuated by the purge control signal from the PCM and controls fuel vapor flow from the canister to the intake manifold.

DTC DESCRIPTION
PCM sets DTC P0444. if the PCM detects that the PCSV control circuit is open.

















MONITOR DTC STATUS

NOTE: If any DTCs (or pending codes) are present, do ALL REPAIRS associated with those codes before proceeding with this troubleshooting free.

1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Press F4(DTAL) to select DTC information from the DTCs menu.
3. Confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.




4. Read "DTC Status" parameter.
5. Is parameter displayed "History(Not Present) fault"?

NOTE:
1. History (Not Present) fault: DTC occurred but has been cleared.
2. Present fault: DTC is occurring at present time.

YES: Fault is intermittent, caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure

NO: Go to "Component Inspection" procedure

COMPONENT INSPECTION
1. Ignition "OFF".
2. Disconnect PCSV connector.




3. Measure resistance between terminals 1 and 2 of the PCSV connector(Component side).
4. Is resistance within the specification?

YES: Go to "W/Harness Inspection" procedure

NO: Check PCSV for contamination, deterioration, or damage. Substitute with a known-good PCSV and check for proper operation. If the problem is corrected, replace PCSV and then go to "Verification of Vehicle Repair" procedure.

TERMINAL AND CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage
3. Has a problem been found?

YES: Repair as necessary and go to "Verification of Vehicle Repair" procedure.

NO: Go to "Power Supply Circuit Inspection" procedure.

POWER SUPPLY CIRCUIT INSPECTION
1. Ignition "ON" & Engine "OFF".




2. Measure voltage between terminal 1 of the PCSV harness connector and chassis ground.
Specification: Approx. B+

3. Is voltage within the specification?

YES: Go to "Control Circuit Inspection" procedure.

NO: Check for a open in the power supply circuit. Repair as necessary and go to "Verification of Vehicle Repair" procedure

CONTROL CIRCUIT INSPECTION
1. Ignition "OFF"
2. Disconnect PCM connector





3. Measure resistance between terminal 2 of the PCSV harness connector and 26 of the PCM harness connector
Specification Approx. 0 Ohm

4. Is resistance within the specification?

YES: Check for poor connection between PCM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "Verification of Vehicle Repair" procedure

NO: Repair as necessary and go to "Verification of Vehicle Repair" procedure

VERIFICATION OF VEHICLE REPAIR
After a repair it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Press F4(DTAL) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
3. Read "DTC Status" parameter.
4. Is parameter displayed "History(Not Present) fault"?

YES: System performing to specification at this time. Clear the DTC.

NO: Go to the applicable troubleshooting procedure.