Diagnostic Test

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

CHECK FOR ANY SERVICE BULLETINS THAT APPLY
1. Before proceeding with this test procedure, complete any Service Bulletins or PCM Flash updates that relate to this fault code.
  Are there any Service Bulletins or PCM Flash updates available?
  
  Yes
  - Complete the applicable Service Bulletins or PCM Flash update.
  - Verify the system is not leaking by performing the ELCM Forced Monitor test.
  No
  - Go To 2
CHECK FOR AN ACTIVE CONDITION
1. Turn the ignition on.
2. With the scan tool, read and record DTCs and Freeze Frame data on the repair order.
3. With the scan tool, erase DTCs.
  NOTE:
  The scan tool test may not run if there are Evaporative System faults present.
4. With the scan tool, Perform the ELCM Forced Monitor test.
  Did the ELCM Forced Monitor test pass or fail?
  
  Passed
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
  Failed
  - Go To 3
TEST WITH THE EELD TESTER TO VERIFY LEAK
NOTE:
Extreme temperatures during leak testing can yield poor results. High fuel temperature, either from a hot engine or extremely high ambient temperature, can cause excessive fuel vaporization which can cause pressure in the system to become too high or unstable and yield poor results that falsely indicate a leak during testing. Extreme cold temperatures could possibly conceal a potential leak during testing. For best results, if one of the previous conditions is true, allow the vehicle to sit inside the shop and achieve a reasonable temperature before checking for leaks. Recommend somewhere between approximately 10°C (50°F) and 30°C (86°F).

WARNING:
Keep lit cigarettes, sparks, flames, and other ignition sources away from the test area to prevent the ignition of explosive gases. Keep the test area well ventilated. Failure to do so may result in possible serious or fatal injury.
1. To continue testing you will need the special tool # 8404C, (EELD and Accessory Kit).
2. Disconnect the hose from the ELCM that is connected to the fresh air side of the system.
3. Connect the appropriate service adapter from the EELD Tester into the hose that connects to the ELCM.
4. Connect the red power lead of the EELD to the Battery positive terminal and the black ground lead to battery negative terminal.
5. Connect shop air to the EELD.
6. Set the smoke/air control switch to AIR .
  NOTE:
  The Evaporative system should not be tested by putting smoke into the system because the residue from the smoke being generated will damage the ELCM.
7. Block the end of the tester's AIR supply tip (clear hose).
8. Press the remote smoke/air start button.
  NOTE:
  The indicator ball should be resting on the bottom of the air flow meter (this is calibrated to no leak present) if the EELD is calibrated correctly.
9. Position the red flag on the air flow meter so it is aligned with the indicator ball (this is calibrated to no leak).
10. When the calibration is complete, release the remote button. The EELD flow meter is now calibrated for no leaks.
11. Disconnect the hose from the ELCM that is connected to the fresh air side of the system.
  NOTE:
  An internal leak through the FTIV can be concealed during the next few steps because the Fuel Tank side will eventually become pressurized causing a pass. To properly test the FTIV for an internal leak, remove the line connected to the Fuel Tank side of the system at the FTIV during the remainder of this test procedure.
12. Connect the appropriate service adapter to the hose.
13. Connect the AIR supply hose from the EELD to the adapter.
14. Press the remote button to activate AIR flow.
15. Compare the flow meter indicator ball reading to the red flag.
  NOTE:
  If the indicator ball drops down to the red flag on air flow meter, that would indicate that the system is sealed and not leaking. If the indicator ball does not drop down to the red flag on air flow meter, continue testing to find the source of the leak.
16. After gathering the results from testing at the ELCM, securely block off the hose that connects to the ELCM.
  NOTE:
  Do not reconnect the line to the ELCM when performing the leak check in the next three tests step. The ELCM is normally vented to atmosphere through the 0.20" Orifice when the Change-Over Valve inside the ELCM is commanded off. Testing at the FTIV or Purge Solenoid with the ELCM connected will result in a small leak result during the leak check with the EELD Tester.
17. Disconnect the line that connects to the FTIV and perform the leak check on the fresh air side again, gathering the results of the leak check. After gathering the results from testing at the FTIV, reconnect the line to the FTIV.
18. Disconnect the line that connects to the Purge Solenoid and repeat the leak test again, gathering the results of the leak check.
19. Disconnect the line that connects to the Charcoal Canister and repeat the leak test again, gathering the results of the leak check.
20. Disconnect the line that connects to the OBD Vent Valve and repeat the leak test again, gathering the results of the leak check.
  Which scenario best describes the results from leak testing at all three points of entry?
  
  System was sealed when tested at the Purge Solenoid but leaking when tested at the ELCM, FTIV, OBD Vent Valve, and Charcoal Canister:
  - Check the vapor line connection at the Purge Solenoid for a poor fit or damaged seal that could be leaking. If the hose connection is good, replace the Purge Solenoid in accordance with the Service Information.
  - With the scan tool, perform the ELCM Forced Monitor test again and verify repair.
  System was sealed when tested at the FTIV but leaking when tested at the Purge Solenoid, ELCM, OBD Vent Valve, and Charcoal Canister:
  - Check the vapor line connection at the FTIV for a poor fit or damaged seal that could be leaking. If the hose connection is good, replace the FTIV in accordance with the Service Information.
  - With the scan tool, perform the ELCM Forced Monitor test again and verify repair.
  System was sealed when tested at the Charcoal Canister but leaking when tested at the Purge Solenoid, ELCM, OBD Vent Valve, and FTIV:
  - Check the vapor line connection at the Charcoal Canister and Hydrocarbon Trap for a poor fit or damaged seal that could be leaking. If the hose connection is good, replace the Charcoal Canister and Hydrocarbon Trap in accordance with the Service Information.
  - With the scan tool, perform the ELCM Forced Monitor test again and verify repair.
  System was sealed when tested at the OBD Vent Valve but leaking when tested at the Purge Solenoid, ELCM, FTIV, and Charcoal Canister:
  - Check the vapor line connection at the FTIV for a poor fit or damaged seal that could be leaking. If the hose connection is good, replace the FTIV in accordance with the Service Information.
  - With the scan tool, perform the ELCM Forced Monitor test again and verify repair.
  System was sealed and not leaking when tested at all three points:
  - Check for a poor fit or connection at the ELCM. If the hose connection to the ELCM is good, replace the ELCM in accordance with the Service Information.
  - With the scan tool, perform the ELCM Forced Monitor test again and verify repair.
  A leak was detected when testing the system at all three points:
  - Check for a poor connection at all of the components in the system. Check the EVAP system lines for leaks. Use the EELD Tester to pressurize the system and check for leaks with soapy water at the lines or connection points to the components in the system.
  - With the scan tool, perform the ELCM Forced Monitor test again and verify repair.