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DTC P0442 or P0455

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 Descriptors

DTC P0442: Evaporative Emission (EVAP) System Small Leak Detected

DTC P0455: Evaporative Emission (EVAP) System Large Leak Detected

Circuit/System Description

This DTC tests the evaporative emission (EVAP) system for a small and large leak when the Vehicle is turned OFF and the correct conditions are met. The propulsion system needs to be OFF for several hours before the small and large leak tests run. The EVAP leak detection pump creates a vacuum across a 0.51 mm (0.020 in) reference orifice. This reference vacuum is then compared to the vacuum level created in the fuel tank to determine if a leak exists

The following table illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP components:

Engine Control Module Command

EVAP Canister Purge Solenoid Valve

EVAP Canister Vent Solenoid Valve

Vacuum Pump

Switch Valve

ON

Open

Open/Venting

Pump Runs

Pump Position/Not Venting

OFF

Closed

Closed/Not Venting

Pump OFF

Vent Position

Conditions for Running the DTC

    • DTCs P043E, P043F, P06E4, P0111, P0112, P0113, P0114, P0117, P0118, P0116, P0119, P0128, P0449, P0498, P0499, P1458, P145A, P145C, P145D, P145E, P145F, P0451, P0452, P0453, P0461, P0462, P0463, P0502, P0503, P0722, P0723, P1459, P2066, P2067, P2068, P2400, P2401, P2402, P2418, P2419, P2420, P2421, P2422, P2450, P2537, P2610, U0140, U182D, U0073, U0074, is not set
    • The barometric pressure (BARO) is between 70-110 kPa (10-16 PSI).
    • The fuel level is between 10-90 %.
    • The ECT is less than 40°C (104°F).
    • The IAT is between 4-45°C (39-113°F).
    • The system voltage is greater than 10 V.
    • Vehicle speed less than 1.6 km/h (1 MPH).
    • A refuelling event needs to be detected prior to running this test --P0455 only.
    • There are three possible time windows for this test to run. Up to that point and through this time period the propulsion system must not be active. These time windows are: 5.0, 7.0 or 9.5 hours.

Conditions for Setting the DTC

P0442

DTC P0442 sets when the EVAP leak detection pump pressure sensor (gauge) vacuum reading is less than the 0.51 mm (0.020 in) reference orifice vacuum measurement plus a calibrated value for greater than 6 min.

P0455

DTC P0455 sets after a refueling event has been detected and the small/large leak diagnostics have not passed. If the EVAP leak detection pump pressure sensor (gauge) vacuum reading is less than the 0.51 mm (0.020 in) reference orifice vacuum measurement and times a calibrated value for greater than 6 min.

Action Taken When the DTC Sets

DTCs P0442 and P0455 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0442 and P0455 are Type B DTCs.

Diagnostic Aids

    • The EVAP system can be filled with smoke more quickly and completely by injecting smoke at the purge tube and commanding the vent solenoid valve open. For example, when injecting smoke at the purge tube, remove the filler cap or temporarily leave the vent solenoid valve open until smoke is observed. Close the system and continue testing. If using a fuel cap adapter at the filler neck, disconnect the purge tube at the EVAP canister purge solenoid valve until smoke is observed.
    • To help locate intermittent leaks, use the EN 41413-200 Evaporative Emissions System Tester to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with a high intensity white light.
    • To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with a high intensity white light.
    • If a small leak is difficult to find, it may be necessary to remove the EVAP components and test them one at a time using the adapters in the GE-41413-300 .

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

    • CH-48096 EVAP Service Access Port Tool
    • GE-41413-300 EVAP Cap And Plug Kit
    • J 41413-200 Evaporative Emissions System Tester
    • GE-41413-SPT High Intensity White Light
    • J 41415-30 Fuel Tank Cap Adapter

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. • Loose, incorrect, missing, or damaged fuel fill cap
    • A damaged EVAP purge solenoid
    • Disconnected, incorrectly routed, kinked, or damaged EVAP pipes and hoses
    • A damaged EVAP vent valve or EVAP canister
         ⇒If you find any of the above conditions, repair as necessary.

    Note: Refer to the J 41413-200 operation manual for detailed instructions in Evaporative Emission Control System Diagnosis

  3. Disconnect the purge tube at the quick connector on the evaporative emission canister side of the Q12 evaporative emission canister purge solenoid valve and install the CH-48096
  4. Connect the J 41413-200 to the CH-48096
  5. Use the flow meter on the J 41413-200 calibrated to 0.51 mm (0.020 in) to determine if there is a leak in the evaporative emission system.
  6. Note: 

       • Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilise.
       • Ensure that the vehicle underbody temperature is similar to the ambient temperature and allow the surrounding air to stabilise before starting the diagnostic procedure. The system flow will be less with higher temperatures.

  7. Use the remote switch to activate the J 41413-200 and compare the flow meter's stable floating indicator position to the red flag. The floating indicator should be below the red flag.
  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

1. Vehicle OFF, turn the nitrogen/smoke valve on the control panel to SMOKE.

2. Vehicle in Service Mode, command the EVAP vent solenoid ON with a scan tool.

Note: 

   • The fuel sender may need to be accessed to inspect some of the EVAP system components.
   • Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilise.
   • Introduce smoke at 15 second intervals while testing the system.

3. Use the remote switch to introduce smoke into the EVAP system.

4. Verify that smoke is not exiting the entire EVAP system with the GE-41413-SPT

If smoke is observed, repair the condition as necessary.

Repair Verification

  1. Install any components or connectors that have been removed or replaced during diagnosis.
  2. Perform any adjustment, programming or setup procedures that are required when a component or module is removed or replaced.
  3. Clear the DTCs
  4. Vehicle OFF, all systems OFF, this may take up to 2 minutes.
  5. Vehicle in Service Mode, seal the EVAP system and use the flow meter on the J 41413-200 , calibrated to 0.51 mm (0.020 in) to determine that there is no leak in the EVAP system. Use the remote switch to activate the J 41413-200 and compare the flow meter's stable floating indicator position to the red flag. The floating indicator should be below the red flag.
  6. If floating indicator is above the red flag, a leak still exists.
  7. If the repair was related to a DTC, duplicate the conditions for running the DTC and use the freeze frame/failure records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Evaporative Emission Canister Vent Solenoid Valve Replacement
    •  Evaporative Emission Canister Replacement
    •  Evaporative Emission Canister Purge Solenoid Valve Replacement
    •  Fuel Tank Fuel Pump Module Replacement
   


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