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Test Description

WARNING: This page is about a different variant/trim than selected.

The numbers below refer to the step numbers on the diagnostic table.

  1. 4:  The EVAP vent solenoid valve is located inside the EVAP canister. The EVAP canister must be removed from the vehicle, to access the EVAP vent solenoid valve. Once the EVAP solenoid vent valve has been removed from the EVAP canister, the electrical connector is re-connected. The vent solenoid valve is observed while being commanded ON and OFF with a scan tool.
DTC P0446 Evaporative Emission (EVAP) Vent System Performance

Step Action Values Yes No
Schematic Reference:  Evaporative Emissions (EVAP) Hose Routing Diagram 
1 Did you perform the Diagnostic System Check-Engine Controls? - Go to Step 2  Go to Diagnostic System Check - Engine Controls
2 Inspect the evaporative emission (EVAP) system for the following conditions:
  • A damaged EVAP vent valve
  • A damaged EVAP canister

Did you find and correct the condition?		 - Go to Step 9  Go to Step 3 
3
  1. Turn OFF the ignition.
  2. Disconnect the purge line from the EVAP canister purge solenoid.
  3. Turn ON the ignition, with the engine OFF.
  4. Observe the Fuel Tank Pressure sensor parameter with a scan tool.
Is the Fuel Tank Pressure sensor parameter within the specified range?		 -1 and +1 in H20 Go to Step 4  Go to Step 8 
4 
  1. Turn OFF the ignition.
  2. Remove the EVAP canister. Refer to Evaporative Emission (EVAP) Canister Replacement .
  3. Remove the EVAP vent valve from the EVAP canister. Refer to Evaporative Emission (EVAP) Canister Vent Solenoid Valve Replacement .
  4. With the EVAP canister removed from the vehicle, connect the EVAP vent valve electrical connector.
  5. Turn ON the ignition with the engine OFF.
    6. IMPORTANT:
    • The EVAP Vent Solenoid Command parameter may not change states when using the EVAP Vent Solenoid output control.
    • The DTCs may need to be cleared if the output control does not operate.
  6. Command the EVAP vent valve ON and OFF with a scan tool.
Does the EVAP vent valve open and close?		 - Go to Step 5  Go to Step 6 
5
  1. Remove the fresh air inlet cover from the EVAP canister.
  2. Inspect the fresh air inlet for a restriction or a blockage.
  3. Inspect the fresh air inlet filter for a restriction or a blockage.
Did you find and correct the condition?		 - Go to Step 9  Go to Step 7 
6 Replace the EVAP vent valve. Refer to Evaporative Emission (EVAP) Canister Vent Solenoid Valve Replacement .
Did you complete the replacement?		 - Go to Step 9  -
7 Replace the EVAP canister. Refer to Evaporative Emission (EVAP) Canister Replacement .
Did you complete the replacement?		 - Go to Step 9  -
8 Replace the fuel tank pressure (FTP) sensor. Refer to Fuel Tank Pressure Sensor Replacement .
Did you complete the replacement?		 - Go to Step 9  -
9
IMPORTANT: Do not exceed the specified value in this step. Exceeding the specified value may produce incorrect test results.
  1. Turn OFF the ignition.
  2. Connect all disconnected components.
  3. Connect the J 41413-200  Evaporative Emissions System Tester (EEST) power supply clips to a known good 12-volt source.
  4. Install the J 41415-40  Fuel Tank Cap Adapter to the fuel fill pipe.
  5. Connect the J 41413-200  Nitrogen/Smoke Supply Hose to the J 41415-40  .
  6. Turn ON the ignition with the engine OFF.
    7. IMPORTANT:
    • The EVAP Vent Solenoid Command parameter may not change states when using the EVAP Vent Solenoid output control.
    • The DTCs may need to be cleared if the output control does not operate.
  7. Command the EVAP vent solenoid closed with a scan tool.
  8. Turn the nitrogen/smoke valve on the J 41413-200  control panel to NITROGEN.
  9. Use the remote switch to pressurize the EVAP system to the first specified value.
  10. Observe the Fuel Tank Pressure sensor parameter with a scan tool.
    11. IMPORTANT:
    • The EVAP Vent Solenoid Command parameter may not change states when using the EVAP Vent Solenoid output control.
    • The DTCs may need to be cleared if the output control does not operate.
  11. Command the EVAP vent solenoid open with a scan tool.
Is the Fuel Tank Pressure sensor parameter less than the second parameter?		 5 in H2O
1 in H2O		 Go to Step 10  Go to Step 2 
10
  1. Clear the DTCs with a scan tool.
  2. Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		   Go to Diagnostic Trouble Code (DTC) List System OK
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