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 provide an overview of each diagnostic category. |
DTC Descriptor
DTC P0455: Evaporative Emission (EVAP) System Large Leak DetectedCircuit/System Description
The control module 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 control module commands the EVAP vent solenoid valve ON and the EVAP purge solenoid valve ON, allowing vacuum into the EVAP system. The control module 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. The following table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP canister purge and vent valves.
Control Module Command | EVAP Canister Purge Valve | EVAP Canister Vent Valve |
|---|---|---|
ON | Open | Closed |
OFF | Closed | Open |
Conditions for Running the DTC
| • | Before the PCM can report DTC P0455 failed, DTC P0496 must run and pass. |
| • | DTCs P0106, P0107, P0108, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0220, P0222, P0223, P0442, P0443, P0449, P0451, P0452, P0453, P0454, P0464, P0496, P0608, P0609, P0641, P0651, P1516, P2101, P2119, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138 are not set. |
| • | The ignition voltage is between 11-18 volts. |
| • | The barometric pressure (BARO) is more than 74 kPa. |
| • | The fuel level is between 15-85 percent. |
| • | The engine coolant temperature (ECT) 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 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
| • | 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 41413-200 to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT . |
| • | To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT . |
| • | 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
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Special Tools Required
| • | J 41413-SPT High Intensity White Light |
| • | J 41413-200 Evaporative Emissions System Tester (EEST) |
| • | J 41413-300 EVAP Cap and Plug Kit |
| • | GE-41415-50 Fuel Tank Cap Adapter |
| • | CH-48096 EVAP Service Access Port Tool |
Circuit/System Testing
Important:
• 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
operation manual for detailed instructions.
- Using the GE-41415-50 , connect the J 41413-200 to the vehicle filler neck.
- 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.
- Start the engine with the J 41413-200 connected to the fuel filler neck.
- Allow the engine to idle.
- Use the Purge/Seal function to seal the system with a scan tool.
- Command the EVAP canister purge solenoid valve to 20 percent.
- The vacuum/pressure gage on the J 41413-200 and the FTP parameter on the scan tool should both show vacuum.
- 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 gage on the J 41413-200 .
| ⇒ | If a leak is detected, use the J 41413-200 to apply smoke to the EVAP system at the service port or the filler neck until the leak is located. 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 . |
| ⇒ | If the vacuum/pressure gage shows vacuum, but the FTP parameter does not show vacuum, replace the FTP sensor. |
| ⇒ | If neither the FTP parameter nor the vacuum/pressure gage shows vacuum, repair the restriction in the purge path. |
| ⇒ | 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 after completing the diagnostic procedure.
