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

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 evaporative emission canister vent solenoid valve ON and the evaporative emission canister purge solenoid valve ON, allowing vacuum into the evaporative emission system. The ECM monitors the fuel tank pressure 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

* Before the ECM can report DTC P0455 failed, DTC P0496 must run and pass.
* DTCs P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0125, P0442, P0443, P0446, P0449, P0452, P0453, P1111, P1112, P1114, P1115, P1125, P1135, P1351, P1352, P1361, P1362, P1516, P1548, P2101, P2107, P2108, P2119, P2120, P2125, P2135, P2138 are not set.
* The engine is running.
* The ignition voltage is between 10-18 volts.
* The barometric pressure (BARO) is more than 75 kPa.
* The fuel level is between 15-85 percent.
* The start-up engine coolant temperature (ECT) is between 4-30°C (39-86°F).
* The start-up intake air temperature (IAT) is between 4-30°C (39-86°F).
* The start-up ECT and IAT are within 9°C (16°F) of each other.
* DTC P0455 runs once per cold start within 10 minutes of start-up.

Conditions for Setting the DTC

The EVAP system is not able to achieve or maintain vacuum for up to 4 times during the diagnostic test.

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, damaged, or incorrect fuel fill cap.
* Inspect for a damaged fuel filler neck seal surface.
* A blockage or restriction in the evaporative emission purge solenoid valve, purge pipe, evaporative emission canister, or vapor pipe, can cause this DTC to set.
* The evaporative emission 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 J 41413-200 - EEST , move all evaporative emission components while observing smoke with the J 41413-SPT - White Light.
* Individual components can be isolated and tested using adapters in the J 41413-300 - Kit.
* A condition may exist where a leak in the evaporative emission 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 evaporative emission system and then observe the fuel tank pressure parameter for vacuum decay.

Reference Information
Schematic Reference

Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
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 (Programming and Relearning)for scan tool information
Description and Operation

Evaporative Emission Control System Description (Evaporative Emission Control System Description)
Special Tools

* CH-48096 EVAP Service Access Port Tool
* GE-41415-50 Fuel Tank Cap Adapter
* J 41413-200 (J 41413-100) Evaporative Emission System Tester (EEST)
* J 41413-300 EVAP Cap and Plug Kit
* J 41413-311 EVAP Plug
* J 41413-VLV EVAP Service Port Vent Fitting
* J 41413-SPT High Intensity White Light

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.
* Refer to the J 41413-200 - EEST operation manual for detailed instructions in Evaporative Emission System Diagnosis (Evaporative Emission System Diagnosis).

1. Connect the J 41413-200 to the vehicle EVAP service port. For vehicles without a service port, disconnect the purge tube at the quick connector on the EVAP canister side of the purge solenoid valve and install the CH-48096 .
2. Seal the EVAP system and use the flow meter on the J 41413-200 , calibrated to 0.51 mm (0.02 in) to determine that there is no leak in the EVAP system.

• If a leak is detected, use the J 41413-200 to apply smoke to the EVAP system at the service port until the leak is located.

3. To test for a restriction, connect the J 41413-200 nitrogen/smoke hose to the J 41413-311 brass cone adapter. Disconnect the hose at the fuel cap end of the GE-41415-50 . Connect the J 41413-311 to the disconnected hose on the GE-41415-50 . Install the GE-41415-50 filler neck end only to the vehicle.
4. Allow the engine to idle.
5. Use the Purge/Seal function to seal the system with a scan tool.
6. Command the EVAP canister purge solenoid valve to 30 percent.
7. The vacuum/pressure gauge on the J 41413-200 and the FTP parameter on the scan tool should both show vacuum.

• If the vacuum/pressure gauge shows vacuum but the FTP parameter does not show vacuum, replace the FTP sensor.
• If neither the FTP parameter nor the vacuum/pressure gauge shows vacuum, repair the restriction in the purge path.

8. Verify that the vacuum increases to the abort limit on the scan tool or more than 3.2 volts, and the value is closely similar between the scan tool and the vacuum/pressure gauge on the J 41413-200 .

• If the values are not similar or the voltage did not reach 3.2 volts, replace the FTP sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Fuel Tank Pressure Sensor Replacement (NU6) (Fuel Tank Pressure Sensor Replacement (NU6))Fuel Tank Pressure Sensor Replacement (NC7) (Fuel Tank Pressure Sensor Replacement (NC7))
* Control Module References (Programming and Relearning)for ECM replacement, setup, and programming