P0455
DTC P0455 (LUW)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P0455
- Evaporative Emission (EVAP) System Large Leak Detected
Circuit/System Description
The engine control module (ECM) tests the evaporative emission (EVAP) system for a large leak. The ECM monitors the fuel tank pressure sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the ECM commands the EVAP canister purge solenoid valve open and the EVAP canister vent solenoid valve closed. This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the ECM commands the EVAP canister purge solenoid closed, sealing the system, and monitors the fuel tank pressure sensor input in order to determine the EVAP system vacuum level. The following table illustrates the relationship between the ON and OFF states, and the open or closed states of the EVAP canister purge solenoid and EVAP canister vent solenoid valves.
Conditions for Running the DTC
* DTCs P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0119, P0122, P0123, P0128, P0222, P0223, P0443, P0449, P0452, P0453, P0454, P0606, P2101, and P16F3 are not set.
* One of the following conditions is met:
- The ignition is off for greater than 12 h.
or
- The start-up intake air temperature (IAT) and the start-up engine coolant temperature (ECT) are within 8°C (14°F).
* The ignition voltage is between 11-32 V.
* The barometric pressure (BARO) is more than 70 kPa (10.15 PSI).
* The start up engine coolant temperature (ECT) is less than 36°C (96.8°F).
* The start up intake air temperature (IAT) is between 4-30°C (39-86°F).
* The EVAP purge is greater than 4.79%.
* The fuel level is between 10-90%.
* The engine run time is less than 17 min.
* The DTC run once an ignition cycle when the above conditions are met.
Conditions for Setting the DTC
The ECM detects the EVAP system is not able to achieve or maintain vacuum during the diagnostic test.
Action Taken When the DTC Sets
DTC P0455 is a Type B DTC.
Conditions for Clearing the DTC
DTC P0455 is a Type B DTC.
Diagnostic Aids
* A fuel fill cap that is left OFF after a fuel fill, will cause this DTC to set.
* A loose, missing, or damaged fuel fill cap can cause this DTC to set.
* A blockage or restriction in the EVAP purge solenoid, purge pipe EVAP canister, or vapor pipe, can cause this DTC to set.
* A temporary blockage in the EVAP purge solenoid, purge pipe or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.
* To help locate intermittent leaks, use the J 4143-200 - Evaporative Emissions System Tester to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with a high intensity white light. Introducing smoke in 15 s intervals will allow less pressure into the EVAP system. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.
* To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 4143-SPT - High Intensity White Light.
* The EVAP system can also be tested from the front of the vehicle using the CH 48096 - EVAP Service Access Port Tool.
* Observe the freeze frame/failure records vehicle mileage since the diagnostic test last failed may help determine how often the condition occurs that caused the DTC to set. This may assist in diagnosing the condition.
Reference Information
Schematic Reference
Engine Controls Schematics (LUW) [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Sunshade - Left (D6I)
Description and Operation
Evaporative Emission Control System Description Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Special Tools
* J 4143-200 - Evaporative Emissions System Tester
* GE 414115-50 - Fuel Tank Cap Adapter
* J 4143-SPT - High Intensity White Light
* CH 48096 - EVAP Service Access Port Tool
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Verification
1. Verify the following conditions do not exist in the EVAP system:
* Loose, incorrect, missing, or damaged fuel fill cap.
* A damaged Q12 Evaporative Emission Purge Solenoid Valve.
* 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.
2. Ignition ON, command the EVAP Purge Solenoid Valve to 50% with a scan tool. You should hear the solenoid click when commanded to 50%.
• If the solenoid does not click, refer to DTC P0443 (LUW) P0443 for further diagnosis.
3. Command the EVAP Vent Solenoid Valve ON and OFF with a scan tool. You should hear the solenoid click when commanded ON and OFF.
• If the solenoid does not click, refer to DTC P0449 (LUW) P0449 for further diagnosis.
4. Engine idling, command the EVAP Purge Solenoid Valve to 50% while observing the scan tool Fuel Tank Pressure Sensor parameter. The reading should indicate a vacuum.
Note: Refer to the J 4143-200 - Evaporative Emissions System Tester operation manual for detailed instructions.
5. Ignition OFF, remove the fuel fill cap. Connect the GE 414115-50 - Fuel Tank Cap Adapter to the fuel tank filler neck. Connect the J 4143-200 - Evaporative Emissions System Tester to the GE 414115-50 - Fuel Tank Cap Adapter.
6. Calibrate the J 4143-200 - Evaporative Emissions System Tester Flow Meter to the correct leak orifice for the vehicle.
7. Turn the nitrogen/smoke valve on the control panel to nitrogen.
Note: Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize.
8. Use the remote switch to activate the J 4143-200 - Evaporative Emissions System Tester and compare the flow meter stable floating indicator position to the red flag. The floating indicator should be below the red flag.
9. 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:
* You must start with the Circuit/System Verification before proceeding with Circuit/System Testing.
* Ensure that the vehicle underbody temperature is similar to the ambient temperature and allow the surrounding air to stabilize before starting the diagnostic procedure. The system flow will be less with higher temperatures.
1. Install the fuel fill cap. Engine idling, command the EVAP Purge Solenoid to 50% while observing the Fuel Tank Pressure Sensor pressure parameter. The reading should indicate a vacuum.
• If no vacuum is indicated perform the following:
1. Ignition OFF, disconnect the EVAP purge pipe from the Q12 Evaporative Emission Purge Solenoid Valve.
2. Engine idling, command the EVAP Purge Solenoid to 50%. Verify vacuum is available to the EVAP purge pipe.
• If no vacuum is available, test the vacuum supply hose for a restriction. If the hose tests normal, replace the Q12 Evaporative Emission Purge Solenoid Valve.
• If vacuum is available, test the EVAP purge pipe between the Q12 Evaporative Emission Purge Solenoid Valve and the fuel tank for a restriction. If the pipe tests normal, replace the B150 Fuel Tank Pressure Sensor.
2. Remove the fuel fill cap. Connect the GE 414115-50 - Fuel Tank Cap Adapter to the fuel tank filler neck. Connect the J 4143-200 - Evaporative Emissions System Tester to the GE 414115-50 - Fuel Tank Cap Adapter.
3. Turn the nitrogen/smoke valve on the control panel to SMOKE.
4. Ignition ON, command the EVAP vent solenoid Valve ON with a scan tool.
Note:
* Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize.
* Introduce smoke at 15 s intervals while testing the system.
* The fuel sender may need to be accessed to inspect some of the EVAP system components.
5. Use the remote switch to introduce smoke into the EVAP system.
6. Verify that smoke is not exiting the entire EVAP system with the J 4143-SPT - High Intensity White Light.
• If smoke is observed, repair the condition as necessary.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Evaporative Emission Canister Replacement Service and Repair
* Evaporative Emission Canister Purge Solenoid Valve Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, programming, and setup