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For 1990-2009 cars only
Makes 🢒 Saturn 🢒 2005 🢒 L300/LW300 🢒 Brakes 🢒 Park Brake 🢒 DTC P0455

Object Number: 1247692 Size: MF
Engine Controls Component Views
Engine Controls Schematics

System Description

The control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister 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 control module commands the EVAP canister purge solenoid valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level decreases too rapidly, this DTC sets.

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 solenoid valves.

Control Module Command

EVAP Canister Purge Solenoid Valve

EVAP Canister Vent Solenoid Valve

ON

Open

Closed

OFF

Closed

Open

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0455 EVAP System Large Leak Detected

Conditions for Running the DTC
    • DTCs P0030, P0031, P0032, P0036, P0037, P0038, P0050, P0051, P0052, P0056, P0057, P0058, P0117, P0118, P0121, P0122, P0123, P0125, P0128, P0131, P0132, P0133, P0134, P0135, P0136, P0137, P0138, P0139, P0140, P0141, P0150, P0151, P0152, P0153, P0154, P0155, P0156, P0157, P0158, P0159, P0160, P0161, P0221, P0222, P0223, P0443, P0446, P0449, P0451, P0452, P0453, P0455, P0458, P0459, P0498, P0499, P0506, P0507, P1271, P1277, P1278, P1282, P1283, P1511, P1516, P1519, P1523, P1526, P1530, P1551, P2100, P2101, P2107, P2119, P2122, P2123, P2127, P2128, P2138, P2176 are not set.
    • The engine is running.
    • The ignition voltage is between 10.5-17.3 volts.
    • The barometric pressure (BARO) is more than 68 kPa.
    • The fuel level is between 15-85 percent.
    • The intake air temperature (IAT) is between 4-35°C (39-95°F).
    • The start-up engine coolant temperature (ECT) and IAT are within 9°C (16°F) of each other.
    • The vehicle speed is 0 km/h (0 mph).

Conditions For Setting the DTC

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

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids
    • If DTC P0442, P0446, P0455 is set, EVAP special functions on the scan tool will not be allowed. Clear the DTCs before performing these tests.
    • The ECM uses the FTP sensor to detect the pressure of fuel vapor in the fuel tank during all parts of the EVAP diagnostic system test. Ensure the FTP sensor is not skewed by verifying FTP sensor on the scan tool is between 2.35-2.85 volts with the ignition ON and the engine OFF.
    • The following are possible causes of a large EVAP leak:
       - The fuel cap is missing, incorrectly installed, or leaking.
       - The EVAP canister vent solenoid valve is stuck open.
       - The EVAP canister purge solenoid valve is stuck closed/blocked or a lack of manifold vacuum to solenoid.
       - The EVAP line/hose connections are disconnected/leaking.
       - The fuel sender O-ring is leaking.
       - The FTP sensor seal is leaking.
    • To help locate intermittent leaks, use the J 41413-200 (J 41413-100) Evaporative Emission System Tester (EEST) to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the High Intensity White Light.
    • To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the High Intensity White Light.
    • Review the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to set occurs. This may assist in diagnosing the condition.
    • For intermittent conditions, refer to Intermittent Conditions .

Step

Action

Values

Yes

No

Schematic Reference: Evaporative Emissions Hose Routing Diagram

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2
  1. Inspect the evaporative emission (EVAP) system for the following conditions:
    2. • Loose, missing, or damaged service port schrader valve
    • Loose, incorrect, missing, or damaged fuel fill cap
    • A damaged EVAP canister purge solenoid valve
  2. Raise the vehicle on a hoist. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Inspect the EVAP system for the following conditions:
    4. • Disconnected, improperly routed, kinked, or damaged EVAP pipes and hoses
    • A damaged EVAP canister vent solenoid valve or EVAP canister

Did you find and correct the condition?

--

Go to Step 16

Go to Step 3

3

Important: Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize.

  1. Turn the nitrogen/smoke valve to nitrogen.
  2. Connect the nitrogen/smoke hose to the 0.5 mm (0.2 in) test orifice on the bottom-front of the J 41413-200 (J 41413-100) Evaporative Emission System Tester (EEST).
  3. Use the remote switch to activate the J 41413-200 (J 41413-100).
  4. Align the red flag on the flow meter with the floating indicator. Use the remote switch to de-activate the J 41413-200 (J 41413-100).
  5. Install the J 41415-40 Fuel Tank Cap Adapter to the fuel fill pipe.
  6. Remove the nitrogen/smoke hose from the test orifice and install the hose onto the J 41415-40 .
  7. Turn ON the ignition, with the engine OFF.
  8. Command the EVAP vent solenoid closed with a scan tool.
  9. Use the remote switch to introduce nitrogen and fill the EVAP system until the floating stabilizes.
  10. Compare the flow meter's stable floating indicator position to the red flag.

Is the floating indicator below the red flag?

--

Go to Step 6

Go to Step 4

4

Important: Ensure that the vehicle underbody temperature is similar to the ambient temperature and allow the surrounding air to stabilize before starting the diagnostic procedure. System flow will be less with higher temperatures.

  1. Turn OFF the ignition.
  2. Connect the J 41413-200 (J 41413-100) power supply clips to a known good 12-volt source.
  3. Install the J 41415-40 to the fuel fill pipe.
  4. Connect the J 41413-200 (J 41413-100) nitrogen/smoke supply hose to the J 41415-40 .
  5. Turn ON the ignition, with the engine OFF.
  6. Command the EVAP vent solenoid valve closed with a scan tool.
  7. Turn the nitrogen/smoke valve on the J 41413-200 (J 41413-100) control panel to SMOKE.
  8. Use the remote switch to introduce smoke into the EVAP system.
  9. Use the J 41413-VLV EVAP Service Port Vent Fitting to open the EVAP service port.
  10. Remove the J 41413-VLV once smoke is observed.
  11. Continue to introduce smoke into the EVAP system for an additional 60 seconds.
  12. Inspect the entire EVAP system for exiting smoke with the High Intensity White Light.
  13. Continue to introduce smoke at 15 second intervals until the leak source has been located.

Did you locate and repair a leak source?

--

Go to Step 17

Go to Step 5

5

  1. Disconnect the J 41415-40 from the fuel fill pipe.
  2. Install the fuel fill cap to the fuel fill pipe.
  3. Connect the J 41413-200 (J 41413-100) nitrogen/smoke supply hose to the EVAP service port.
  4. Use the remote switch to introduce smoke into the EVAP system.
  5. Inspect the entire EVAP system for exiting smoke with a High Intensity White Light.
  6. Continue to introduce smoke at 15 second intervals until the leak source has been located.

Did you locate and repair a leak source?

--

Go to Step 17

Go to Step 6

6

  1. Use the remote switch to stop introducing smoke.
  2. Install the J 41415-40 to the fuel fill pipe.
  3. Connect the J 41413-200 (J 41413-100) nitrogen/smoke supply hose and vehicle fuel fill cap to the J 41415-40 .
  4. Command the EVAP canister vent solenoid valve open with a scan tool.
  5. Compare the fuel tank pressure sensor parameter with a scan tool to theJ 41413-200 (J 41413-100) pressure/vacuum gage.

Is the scan tool fuel tank pressure sensor parameter within the specified value of the J 41413-200 (J 41413-100) pressure/vacuum gage?

+1 to -1 in H2O

Go to Step 7

Go to Step 13

7
  1. Seal the EVAP system using the EVAP Purge/Seal function with a scan tool.
  2. Turn the nitrogen/smoke valve on the J 41413-200 (J 41413-100) control panel to NITROGEN.
  3. Use the J 41413-200 (J 41413-100) to pressurize the EVAP system to the first specified value.

Is the fuel tank pressure sensor parameter more than the second specified value?

10 in H2O

5 in H2O

Go to Step 8

Go to Step 13

8
  1. Use the remote switch to stop introducing nitrogen into the EVAP system.
  2. Increase the EVAP canister purge solenoid valve to 100 percent.

Is the fuel tank pressure sensor parameter less than the specified value?

1 in H2O

Go to Diagnostic Aids

Go to Step 9

9

Disconnect the EVAP purge pipe from the EVAP canister purge solenoid valve.

Is the fuel tank pressure sensor parameter less than the specified value?

1 in H2O

Go to Step 14

Go to Step 10

10

Disconnect the EVAP purge pipe at the EVAP canister.

Is the fuel tank pressure sensor parameter less than the specified value?

1 in H2O

Go to Step 15

Go to Step 11

11

Disconnect the EVAP vapor pipe at the EVAP canister.

Is the fuel tank pressure sensor parameter less than the specified value?

1 in H2O

Go to Step 16

Go to Step 12

12

Repair the pinched or obstructed EVAP vapor pipe.

Did you complete the repair?

--

Go to Step 17

--

13

Replace the fuel tank pressure (FTP) sensor. Refer to Fuel Tank Replacement .

Did you complete the replacement?

--

Go to Step 17

--

14

Replace the EVAP canister purge solenoid valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement .

Did you complete the replacement?

--

Go to Step 17

--

15

Repair the restriction in the EVAP purge pipe.

Did you complete the repair?

--

Go to Step 17

--

16

Replace the EVAP canister. Refer to Evaporative Emission Canister Replacement .

Did you complete the replacement?

--

Go to Step 17

--

17

Important: Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize.

  1. Turn the nitrogen/smoke valve to nitrogen.
  2. Connect the nitrogen/smoke hose to the 0.5 mm (0.2 in) test orifice on the bottom-front of the J 41413-200 (J 41413-100).
  3. Use the remote switch to activate the J 41413-200 (J 41413-100).
  4. Align the red flag on the flow meter with the floating indicator. Use the remote switch to de-activate the J 41413-200 (J 41413-100).
  5. Install the J 41415-40 to the fuel fill pipe.
  6. Remove the nitrogen/smoke hose from the test orifice and install the hose onto the J 41415-40 .
  7. Turn ON the ignition, with the engine OFF.
  8. Command the EVAP canister vent solenoid valve closed with a scan tool.
  9. Use the remote switch to introduce nitrogen and fill the EVAP system until the floating stabilizes.
  10. Compare the flow meter's stable floating indicator position to the red flag.

Is the floating indicator below the red flag?

5 in H2O

Go to Step 18

Go to Step 4

18

Observe the fuel tank pressure sensor parameter with a scan tool.

Is the scan tool fuel tank pressure parameter within the specified value of the J 41413-200 (J 41413-100) pressure/vacuum gage?

1 in H2O

Go to Step 19

Go to Step 6

19
  1. Observe the J 41413-200 (J 41413-100) pressure/vacuum gage.
  2. Increase the EVAP canister purge solenoid valve to 100 percent.

Does the pressure decrease?

--

Go to Step 20

Go to Step 9

20

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

System OK