Chevrolet Trax: DTC 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 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 or restrictions to the purge path in the EVAP system. The ECM commands the EVAP purge solenoid valve open and the EVAP 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 purge solenoid closed, sealing the system, and monitors the fuel tank pressure (FTP) 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 purge and vent solenoid valves.

Conditions for Running the DTC

• DTCs P0068, P00C8, P00C9, P010C, P010D, P012B, P012C, P012D, P0101, P0102, P0103, 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, P0606, P0722, P0723, P1104, P1221, P1682, P2100, P2101, P2102, P2103, P2135, P2176, P160D, P160E, P16A0, P16A1, P16A2 and P16F3 are not set.
• The cold startup engine coolant temperature (ECT) and the startup intake air temperature (IAT) are within 8ºC (46ºF).
• The ignition voltage is between 11-32 V.
• The barometric pressure (BARO) is greater than 70 kPa .
• The start up engine coolant temperature (ECT) is less than 35ºC (95ºF).
• The start up intake air temperature (IAT) is between 4-30ºC (39-86ºF).
• The EVAP purge is greater than 2.80%.
• The fuel level is between 10-90%.
• DTC P0455 runs once per cold start, for up to 17 min, 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.
• After setting the DTC for the first time, 2 L (0.5 gal) of fuel must be consumed before setting the DTC for the second time.
• With a DTC P0455 detected a weak vacuum follow-up test (fuel cap replacement test) will run and passes if tank vacuum is greater than 2.74 kPa (11 in H20). This test will run for a maximum of 22 min. This test runs until it passes.

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

• Inspect for a loose, missing, incorrect, or damaged fuel fill cap.
• Inspect for a damaged fuel filler neck seal surface.
• A blockage or restriction in the EVAP purge solenoid valve, purge pipe, EVAP 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. For example, when injecting smoke at the service port remove the fuel fill cap, or temporarily leave the vent open, until smoke is observed, then close the system and continue testing. If using a fuel cap adapter at the filler neck, use the J 41413-VLV at the service port to allow the system to fill faster.
• To help locate intermittent leaks, use the GE 41413-A to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the GE 41413-SPT .
• Individual components can be isolated and tested using adapters in the J 41413-300 .
• When servicing the EVAP system, test pressure must not exceed 13 in H20 (0.5 PSI) as pressure in excess of this could cause system components to perform inaccurately.
• 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 parameter for vacuum decay.

Reference Information

Schematic Reference

Engine Controls Schematics (Encore) , Engine Controls Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Evaporative Emission Control System 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 (LUV) , Powertrain Diagnostic Trouble Code (DTC) Type Definitions (2H0)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

• GE 41413-A Evaporative Emissions System Tester (EEST)
• CH 48096 EVAP Service Access Port Tool
• GE 41415-30 Fuel Tank Cap Adapter
• J 41413-300 EVAP Cap And Plug Kit
• GE 41413-SPT High Intensity White Light
• J 41413-311 EVAP Plug (Brass Nozzle)
• J 41413-VLV EVAP Service Port Vent Fitting

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) .

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 operation manual for detailed instructions in Evaporative Emission Control System Diagnosis.

1. Disconnect the purge tube at the quick connector on the EVAP canister side of the purge solenoid valve and install the CH 48096
2. Connect the GE 41413-A to the vehicle EVAP service port adapter.
3. Command the EVAP Purge/Seal function to System Seal with a scan tool to seal the EVAP system.
4. Verify that there is no leak in the EVAP system using the flow meter on the GE 41413-A , calibrated to 0.51 mm (0.020 in).

• If a leak is detected

1. Apply smoke to the EVAP system at the service access port adapter with the GE 41413-A .
2. Locate the leak using the GE 41413-SPT .

• When the leak is located, repair or replace the affected component as necessary.

No leak detected

NOTE: The steps below test for a restriction in the purge path.

5. Connect the GE 41413-A nitrogen/smoke hose to the J 41413-311 .
6. Disconnect the hose at the fuel cap end of the GE 41415-30 and connect to the J 41413-311 .
7. Install the GE 41415-30 , filler neck end only, to the vehicle.
8. Engine idling, command the Purge/Seal function to System Seal with a scan tool to seal the system.
9. Command the EVAP Purge Solenoid Valve to 30 % with a scan tool.
10. Verify the vacuum/pressure gauge on the GE 41413-A and the scan tool Fuel Tank Pressure Sensor parameter both show vacuum.

• If the vacuum/pressure gauge shows vacuum, and the Fuel Tank Pressure Sensor parameter does not show vacuum

Replace the B150 Fuel Tank Pressure Sensor.

• If both the Fuel Tank Pressure Sensor parameter and the vacuum/pressure gauge do not show vacuum

Repair the restriction in the purge path.

11. Verify that the Fuel Tank Pressure Sensor parameter increases to greater than 3.2 V, and the pressure values are similar between the scan tool Fuel Tank Pressure Sensor and the vacuum/pressure gauge on the GE 41413-A

• If not within the specified range

Replace the B150 Fuel Tank Pressure Sensor.

• If within the specified range

12. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Tank Pressure Sensor Replacement
• Control Module References for ECM replacement, programming and setup

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