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P0447

DTC P0447 EVAP, EMISSION SYSTEM-VENT CONTROL CIRCUIT OPEN

Component Location:






GENERAL DESCRIPTION
The evaporative emissions 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 Canister Closing Valve (CCV) closes off the air inlet into the canister for leak detection of the evaporative emission system. The CCV also prevents fuel vapors from escaping from the canister. When the engine purges the HC vapors from the canister, the clean air comes into the canister through the canister air-filter and the CCV.

DTC DESCRIPTION
ECM sets DTC P0447 if the ECM detects that the CCV control line is open.

DTC Detecting Condition:






Specification:






Schematic Diagram:






MONITOR DTC STATUS
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:
- History (Not Present) fault : DTC occurred but has been cleared.
- Present fault : DTC is occurring at present time.

YES - Fault is intermittent, caused by poor contact in the sensor's and/or ECM's connector or was repaired and ECM 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 next step as below

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




3. Measure resistance between terminals 1 and 2 of the CCV connector (Component side)

Specification : Approx. 19.8 - 21.8 Ohms at 20 °C(68 °F)

4. Is resistance within the specification?

YES - Go to next step as below

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

POWER CIRCUIT INSPECTION
1. Ignition "ON" & Engine "OFF".
2. Measure voltage between terminal 2 of the CCV harness connector and chassis ground.

Specification : Approx. 5 V

3. Is voltage within the specification?

YES - Go to next step as below

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

CONTROL CIRCUIT INSPECTION
1. Measure voltage between terminal 1 of the CCV harness connector and chassis ground

Specification : Approx. 4 - 5 V

2. Is voltage within the specification?

YES - Go to next step as below

NO - Repair as necessary and 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 - Check for poor connection between ECM 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

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.