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DTC P0497

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0497: Evaporative Emission (EVAP) System No Flow During Purge

Circuit/System Description

This DTC tests for proper inlet manifold vacuum flow to the evaporative emission (EVAP) system. The engine control module (ECM) opens the EVAP canister purge solenoid valve and the EVAP canister vent solenoid valve. The ECM then monitors the fuel tank pressure (FTP) sensor and EVAP leak detection pump pressure sensor to determine if a vacuum is being drawn on the EVAP system. If vacuum in the EVAP system is less than a predetermined value within a predetermined time, this DTC sets.

Conditions for Running the DTC

    • DTCs P0068, P0071, P0072, P0073, P0106, P0107, P0108, P0122, P0123, P0222, P0223, P0443, P0449, P0451, P0452, P0453, P0455, P0458, P0459, P0498, P0499, P0502, P0503, P0606, P0722, P0723, P16F3, P1104, P1458, P1459, P145A, P145D, P145E, P2100, P2101, P2102, P2103, P2400, P2401, P2402, P2418, P2419, P2420, P2422, P2450 is not set.
    • The EVAP purge solenoid is open.
    • The EVAP vent solenoid is open.
    • The EVAP leak detection pump switching valve transitions from vent to not vent, pumping, to vent.
    • The EVAP leak detection pump is OFF.
    • The ignition voltage is greater than 11 volts.
    • The barometric pressure (BARO) is between 70-110 kPa (10-16 PSI).
    • The outside air temperature is between 4-35°C (39-95°F).
    • The engine RPM to enable is between 1500-3400
    • The engine RPM to re-enable is between 1600-3300
    • The engine vacuum to enable is between 10-37 kPa (1.5-5.4 PSI)
    • The engine vacuum to re-enable is between 11-35 kPa (1.6-5.1 PSI)
    • The engine airflow to enable is between 9-34 gps
    • The engine airflow to re-enable is between 10-32 gps
    • The purge flow to enable is greater than 0.14 gps
    • The purge flow to re-enable is greater than 0.13 gps
    • The purge duty cycle to enable is greater than 15 %
    • The purge duty cycle to re-enable is greater than 16 %
    • The requested purge flow to enable is greater than 1.45 %
    • The delivered purge flow to re-enable is greater than 1.40 %
    • The delivered purge flow to enable is greater than 1.10 %
    • The engine is running
    • The purge is enabled
    • The refuelling request button is not pressed
    • The device control is less than 0.5 seconds
    • The fuel tank protection is not active.

DTC P0497 will run once per trip with propulsion system active and engine ON.

Conditions for Setting the DTC

After an initial time delay of 3 s when the FTP sensor reading is greater than 0.39 kPa (0.056 PSI)

Or

After an initial time delay of 3 s when the FTP sensor reading is less than 0.39 kPa (0.056 PSI), plus an EVAP leak detection pump switching valve delay time of 0.2 s.

If the EVAP leak detection pump pressure sensor, gauge, indicates a vacuum change less than 2 kPa (0.29 PSI) for 20 s, then a low purge flow failure has been detected.

Action Taken When the DTC Sets

DTC P0497 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0497 is a Type B DTC.

Diagnostic Aids

    • A temporary blockage in the EVAP canister purge solenoid valve, purge pipe or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.
    • A EVAP vent solenoid valve stuck closed can cause this DTC to set.
    • A EVAP leak detection pump switching valve stuck in the vent or pump position can cause this DTC to set.
    • A fuel tank fuel pump module assembly not fully seated in the fuel tank can cause this DTC to set.
    • A loose fuel cap can cause this DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Evaporative Emission Control System Description

Hybrid Modes of Operation Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

    • J 41413-200 Evaporative Emissions System Tester (EEST)
    • GE-41413-300 EVAP Cap And Plug Kit
    • GE-41413-SPT High Intensity White Light
    • CH-48096 EVAP Service Access Port Tool

For equivalent regional tools, refer to Special Tools : Diagnostic Tools .

Circuit/System Verification

  1. Verify the following conditions do not exist in the EVAP system:
  2. • A loose, missing, or damaged fuel fill cap.
    • A stuck closed, blocked, or restricted EVAP canister purge solenoid valve.
    • A blockage or restriction in the EVAP canister purge solenoid valve vacuum supply hose, purge pipe, EVAP canister or vapor pipe.
         ⇒If you find any of the above conditions, repair as necessary.

    Note:  Refer to EN 41413-200 Evaporative Emissions System Tester operation manual for detailed instructions in Evaporative Emission Control System Diagnosis

  3. Connect the CH-48096 to the EVAP purge solenoid valve. Connect the J 41413-200 to CH-48096 .
  4. Be sure the EVAP leak detection pump switching valve is in the vent position and the vent solenoid is open.
  5. Use the flow meter on the J 41413-200 calibrated to 0.51 mm (0.020 in) to determine there is no leak in the EVAP system.
  6. If a leak is detected, use the J 41413-200 to apply smoke to the EVAP system until the leak is located following the Evaporative Emission Control System Diagnosis .
  7. To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the GE-41413-SPT .
  8. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

Circuit/System Testing

Note: Perform the Circuit/System Verification before proceeding with the Circuit/System Testing.

  1. Remove the J 41413-200 installed during verification then install a vacuum gauge to the CH-48096
  2. Engine running observe the vacuum gauge. Vacuum should not be present.
  3. If there is vacuum present test or replace the Q12 EVAP purge solenoid valve.
  4. Observe the vacuum gauge while commanding the Q12 EVAP purge solenoid valve on with the scan tool. Vacuum should be present from 10-100 %
  5. If no vacuum is present test or replace the Q12 EVAP purge solenoid valve.
  6. Command the EVAP Test and observe the FTP sensor voltage with a scan tool. The FTP sensor parameter should be less than 0.60 volts within 60 seconds.
  7. If the FTP sensor parameter is less than the specified range, repair the blocked purge path.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Evaporative Emission Canister Purge Solenoid Valve Replacement
    •  Evaporative Emission Canister Vent Solenoid Valve Replacement
    •  Evaporative Emission Canister Replacement
    •  Evaporative Emission System Vacuum Leak Detection Pump Replacement
   


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