P0455
DTC P0455
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 ECM tests the evaporative emission (EVAP) system for a large leak or restrictions to the purge path in the EVAP system. When the enabling criteria has been met the ECM commands the EVAP vent solenoid valve ON and the purge solenoid valve ON, allowing vacuum into the EVAP system. The ECM monitors the fuel tank pressure (FTP) sensor voltage to verify that the system is able to reach a predetermined level of vacuum within a set amount of time.
Conditions for Running the DTC
* DTCs P00C8, P00C9, P0068, P012B, P012C, P012D, P0101, P0102, P0103, P010C, P010D, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0121, P0122, P0123, P0125, P0128, P0191, P0192, P0193, P0222, P0223, P0443, P0449, P0452, P0453, P0454, P0502, P0503, P0601, P0604, P0722, P0723, P16A0, P16A1, P16A2, P16F3, P160D, P160E, P1104, P1221, P1682, P2100, P2101, P2102, P2103, P2135, P2176 is not set.
* The ignition voltage is greater than 11 V.
* The barometric pressure (BARO) is greater than 70 kPa.
* The fuel level is between 10-90 %.
* The purge flow is greater than 1.5 %
* The engine coolant temperature (ECT) at start-up is less than 35°C (95°F).
* The intake air temperature (IAT) is between 4-30°C (39-86°F).
* DTC P0455 runs once per cold start when the above conditions are met.
Conditions for Setting the DTC
* The EVAP system is not able to achieve or maintain a calibrated level of vacuum within a set amount of time.
* 2 L (0.5 gal) of fuel must be consumed before setting this DTC a second time.
Action Taken When the DTC Sets
DTC P0455 is a Type B DTC.
Conditions for Clearing the MIL/DTC
DTC P0455 is a Type B DTC.
Diagnostic Aids
* Inspect for a loose, missing or damaged, capless fuel fill flappers.
* A blockage or restriction in the EVAP purge solenoid valve, purge pipe, canister, or vapor pipe, can cause this DTC to set.
* The EVAP system can be filled with smoke more quickly and completely by opening the system opposite the end where the smoke is injected. Close the system once smoke is observed.
* To help locate intermittent leaks using the GE 41413-A - Evaporative Emissions System Tester (EEST), move all EVAP components while observing smoke with the GE 41413-SPT - High Intensity White Light.
* Individual components can be isolated and tested using adapters in the GE 41413-300 - Evaporative Emissions Cap and Plug Kit.
* A condition may exist where a leak in the EVAP system only exists under a vacuum condition. This type of leak may be detected by using the scan tool Purge/Seal function to create a vacuum in the EVAP system and then observe the FTP sensor parameter for vacuum decay.
Reference Information
Schematic Reference
Engine Controls Schematics (LFX) [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Description and Operation
Evaporative Emission Control System Description Evaporative Emission Control System Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* 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
* CH 44284-2 - Fuel Flapper Door Holder
* CH 48096 - Evaporative Emissions Service Access Port Tool
* GE 41413-A - Evaporative Emissions System Tester (EEST)
* GE 41413-SPT - High Intensity White Light
* GE 41413-300 - Evaporative Emissions Cap and Plug Kit
* J 41413-VLV - Evaporative Emissions Service Port Vent Tool
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Testing
Note:
* Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize or produce smoke from a leak.
* Refer to the GE 41413-A - Evaporative Emissions System Tester (EEST) operation manual for detailed instructions in Evaporative Emission System Diagnosis Evaporative Emission System Diagnosis.
Note: This vehicle has a capless fuel fill design that requires the use of CH 44284-2 - Fuel Flapper Door Holder to hold the two flapper valves open.
* Install this tool so that the raised rib nests just inside the flapper door outer lip. The flappers will hold it in place.
* Be careful the force of the flapper doesn't push the tool back out.
* Do not insert tool any further into the fuel neck or it may get stuck or fall into the lower fill tube.
1. Disconnect the purge tube at the quick connector on the EVAP canister side of the Q12 Evaporative Emission Purge Solenoid Valve. Install the CH 48096 - Evaporative Emissions Service Access Port Tool between the disconnected purge tube and the purge solenoid valve. Connect the GE 41413-A - Evaporative Emissions System Tester (EEST) to the service access port tool.
2. Use a scan tool to seal the EVAP system.
3. Use the flow meter on the GE 41413-A - Evaporative Emissions System Tester (EEST), calibrated to 0.51 mm (0.020 in) to determine that there is no leak in the EVAP system.
• If a leak is detected, use the GE 41413-A - Evaporative Emissions System Tester (EEST) to apply smoke to the EVAP system at the purge tube until the leak is located using the GE 41413-SPT - High Intensity White Light.
4. To test for a restriction, allow the engine to idle.
5. Use the Purge/Seal function to seal the system with a scan tool.
6. Command the EVAP purge solenoid valve to 30 %.
7. Verify the FTP parameter on the scan tool shows a vacuum.
• If the FTP parameter does not show vacuum, using GE 41413-A - Evaporative Emissions System Tester (EEST) verify that smoke will exit the CH 44284-2 while it is holding the fuel fill flapper doors open.
• If smoke is present, test or replace the Q12 Evaporative Emission Purge Solenoid Valve.
• If no smoke is present repair the restriction in the purge path.
8. Verify that the vacuum increases to more than 3.2 V on the scan tool.
• If the voltage did not reach 3.2 V, replace the B150 Fuel Tank Pressure Sensor.
Component Testing
Static Test
1. Ignition OFF, disconnect the harness connector at the Q12 Evaporative Emission Purge Solenoid Valve.
2. Test for 10-30 ohms between the control terminal and the ignition terminal.
• If not between 10-30 ohms, replace the Q12 Evaporative Emission Purge Solenoid Valve.
Dynamic Test
1. Ignition OFF, disconnect the harness connector at the Q12 Evaporative Emission Purge Solenoid Valve.
2. Install a 3 A fused jumper wire between the ignition, terminal and 12 V. Install a jumper wire between the control terminal and ground.
3. Verify the EVAP Purge Solenoid Valve turns On & Off/clicks and flows vacuum.
• If the EVAP Purge Solenoid Valve does not turn On & Off/click or flow vacuum, replace the Q12 Evaporative Emission Purge Solenoid Valve.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Evaporative Emission Canister Purge Solenoid Valve Replacement Service and Repair
* Fuel Tank Pressure Sensor Replacement (FWD) Service and RepairFuel Tank Pressure Sensor Replacement (AWD) Service and Repair