Diagnostic Test

1. Before proceeding with this test procedure, perform any Service Bulletins or PCM Flash updates that relate to this fault code.

   Are there any Service Bulletins or PCM Flash updates available?

   Yes 

   • Perform the applicable Service Bulletins or PCM Flash update.
   • Verify the system is not leaking by leak testing the system, Go To  2

   No 

   • Go To  2

1. Turn the ignition on.
2. With the scan tool, navigate to the Small Leak Verification Test routine and follow the instructions on the screen.
   NOTE:

   The routine tests the system using similar methodology as the manual leak evaluation in the next test step with one exception. The routine is based solely on the pressure reading from the FTP Sensor. The ESIM Switch state is not factored into the decision in the routine even though it is solely used for leak detection by the PCM. The ESIM state is shown and documented so that it can be verified for proper operation using the information provided in the table in test step 3 below.

3. Document the results from each phase recorded in the Small Leak Verification Test routine.

   Small Leak Verification Test results?

   Passed 

   • This indicates that the system may be sealed and not leaking. Compare the results from the routine to the expected results and possible failures in the table below in test step 3. If the system is functioning properly, no attempt at a repair should be performed.

   Failed 

   • Compare the results from the routine to the expected results and possible failures in the table below in test step  3.

   Not available on scan tool or will not run 

   • Go To  3

NOTE:

For best results when testing the Fuel Tank should have less than 95% of Fuel Tank capacity.

NOTE:

The results of these checks are subjective, not absolute. They can vary based on the size of the Fuel Tank and system, fuel volume, barometric pressure, ambient and fuel temperature. These conditions should be accounted for when analyzing the results and making your determination if the system has a leak.

2. There are 5 test phases that will be performed. The timing of each phase is important. Take time to read and understand each phase before beginning the test. There are three data reads in the Data Display tab of the scan tool that are referenced to monitor and document during this test.
   • Purge Duty Cycle % - This is monitored to determine if purging is on or off
   • ESIM Switch State
   • Fuel Tank Pressure: Pa
3. The short or simple version of the 5 phases are as follows:
   • Vent the system and document the ESIM and FTP Sensor data reads.
   • Monitor and document the ESIM state and FTP Sensor data reads for 2-3 minutes.
   • Start the engine and document the ESIM state and FTP Sensor data reads immediately after engine starts (before purge is active).
   • Allow purging to become active just long enough to create maximum vacuum and document the ESIM state and FTP Sensor data.
   • Turn engine off, monitor and document the ESIM state and FTP Sensor data reads for 3-4 minutes.
     NOTE:

     These are explained in more detail below along with helpful tips and alternative methods for some of the test phases to try and account for all possible systems and functionalities. Compare the results of each phase to the expected results and possible failures in the table below.

4. Test Phase 1 (Check Zero Reference of FTP Sensor):  With the ignition on vent the system to atmosphere and monitor the data reads. Document the ESIM Switch state and Fuel Tank Pressure Sensor reading.
   • This can be done by removing the gas cap, opening the capless filler or actuating the purge solenoid for one minute  with the scan tool. Actuating the purge solenoid allows not disturbing any components that could be a possible leak point. However, it does not vent quickly on all systems and can take a minute to reach atmosphere.
   • The FTP sensor reading may not be exactly at zero.  This is normal. Whatever the reading is when it is vented is the zero reference.
5. Test Phase 2 (Non-intrusive leak check):  Monitor readings for 2-3 minutes with ignition on, engine not running, after the system is closed. Document the Fuel Tank Pressure Sensor reading.
   • Even if the system appears to be normal and not leaking at this point it is best to continue to check the operation of the entire system.
   • A change of more than 200 Pa in 1 minute would indicate the system is too unstable to accurately test.
6. Test Phase 3 (Purge Solenoid leak check):  Start the engine and monitor and document the ESIM Switch state and Fuel Tank Pressure Sensor reading within 5-10 seconds after the engine is started while the purge solenoid is off  .
   • A small amount of vacuum is created due to fuel being pulled from the tank. (Typically between approximately -25 and -50 Pa).
7. Test Phase 4 (Starting the Intrusive leak check - Also checking ESIM Switch function and General Evap failure):  Allow purging to become active long enough to create maximum vacuum and stabilize. Shut off engine immediately after maximum vacuum is achieved. Should reach approximately -600 Pa. Document the ESIM Switch state and Fuel Tank Pressure Sensor reading.
   • This phase can be done several ways. It is important to get purging to happen in the shortest time possible to keep from generating too much heat in the fuel and Fuel Tank. This can cause the vacuum to decay too quickly in the next test phase and lead to misleading findings.
   • Engine purging is different for each engine and vehicle configuration. Some vehicles will start purging naturally shortly after engine is started. Other engines will need to have the engine speed increased for purging to happen.
   • The recommended method would be to turn the engine off after writing down the ESIM Switch state and FTP Sensor reading in Test Phase 3. Navigate to the Systems Tests and run the "Purge Vapors System Test" and follow the on-screen instructions. Once purge is activated and vacuum is created turn the engine off and navigate back to the data reads in Data Display.
8. Test Phase 5 (Intrusive leak check):  Once max vacuum is created and stable, turn off engine and monitor the FTP Sensor and ESIM Switch readings for an additional 3-4 minutes. Document the ESIM Switch state and Fuel Tank Pressure Sensor reading immediately after engine is turned off and after 3-4 minutes

   Analyze the results recorded from the scan tool or manual system tests above: Listed in the table are the expected results and various failures that can possibly occur

   • TEST PHASE	EXPECTED RESULTS	ACTUAL RESULTS / POSSIBLE FAILURES
     1	ESIM Switch should be open and FTP sensor should read near zero.	If the ESIM switch is reading closed at this point it would indicate 1 of 3 failure modes. The ESIM signal wire is shorted to ground. The ESIM switch is stuck in the closed position. Purge solenoid did not open if actuated. A good indication of this would be if the fuel tank pressure did not change as well.
     2	The fuel tank pressure reading should start to slowly change positive or negative. NOTE: More than a 200 Pa change in 1 minute would indicate the system is too unstable to accurately test. If the system is not leaking it should start to slowly create pressure or vacuum depending on whether it is heating up or cooling down.	A steady value would indicate either a leak is present, or the system temperature is too stable to cause a change. Continue testing to determine if system is leaking.  A very rapid pressure change would indicate that the temperature change is too large causing an invalid result. NOTE: This can occur if bringing a vehicle from outside during a cold ambient temp into a warm shop or very hot ambient temperature into a cooler shop condition. If the vehicle was at operating temperature it will create excessive heat in the system as well.
     3	A small amount of vacuum is created due to fuel being pulled from the tank. (Typically is between approximately -25 and -50 Pa).	If vacuum is created instantly after engine is started near or below the ESIM regulation point (-500 PA) it would indicate that the purge solenoid is leaking. NOTE: Since the purge performance diagnostics look for a delta change in the FTP Sensor signal when purge is commanded on, and again when it is commanded off, this condition may also cause a P0441-Purge System Performance fault to set.
     4	The fuel tank pressure should drop quickly to approximately -600 Pa and the ESIM Switch state changes to closed. NOTE: It is normal for the vacuum to go slightly below the regulation point. when the engine is purging.	If the fuel tank pressure drops as expected but the ESIM switch does not close it would indicate that the switch is stuck open, or an open in the ESIM signal or ground circuit. Note: This condition can also cause the P0440-General Evap System Failure DTC to set since that fault occurs when the ESIM switch does not close when the PCM performs the large leak diagnostic.  If the ESIM switch closes but the fuel tank pressure changes very little or not at all it would indicate a restriction in one of the lines between the canister and FTP sensor or a faulty (stuck) sensor. Before condemning a sensor verify that the 5-Volt supply is present at the sensor. If the 5-Volt supply is not present to the sensor it can cause the sensor signal to stick mid-range and not change. If the ESIM switch does not close and the fuel tank pressure does not change or changes very little it would indicate either a very large leak or the purge solenoid is not opening when actuated. Note: This condition can also cause the P0440-General Evap System Failure DTC to set.  If the vacuum created is 2 to 3 times the expected reading it would indicate the Canister vent hose or fresh air filter are plugged or the ESIM vacuum vent valve is stuck closed. This would also lead to difficulty filling the Fuel Tank during refueling
     5	The FTP Sensor reading should quickly return to the vacuum relief regulation point (approximately -500 Pa) and stabilize. NOTE: The weights can sometimes bounce when the purge solenoid is suddenly shut off causing the vacuum to drop below -500 Pa. The vacuum should stay below approximately -250 Pa and the ESIM switch should remain closed for the additional 3-4 minutes of monitoring.	If the fuel tank pressure reading rises quickly near zero or above -250 Pa and the ESIM switch opens within the 3-4 minutes it would indicate that the system has a leak. Go To  4. If the expected results were attained during each phase of testing the system is most likely not leaking at this time. Some possible causes for the false failure could be: Software issues. Check for any Service Bulletins that may apply. Debris was stuck in the purge solenoid or one of the ESIM relief valves that has since cleared. The ESIM is not mounted correctly with the switch at the 3 o'clock position causing the relief valves not to seal properly.

What is the preferred method to leak check the system?

Leak test the entire system as a whole: 

• Go To  5

Split the system at the Charcoal Canister and leak test: 

• Go To  6

1. To continue testing you will need the (special tool #8404C, Kit, EELD And Accessory)
2. Connect the red power lead of the EELD to the Battery positive terminal and the black ground lead to Battery negative terminal.
3. Connect shop air to the EELD.
4. Set the smoke/air control switch to AIR  to pressurize the system.
5. Press the remote smoke/air start button.
6. Block off the end of the tester's AIR supply tip (clear hose) while pressing the remote 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.

7. If the indicator ball is not resting on the bottom of air flow meter, position the red flag on the air flow meter so it is aligned with ball.
8. Connect the service adapter (special tool #8404-ADP, Smoke Machine Adapters) to the ESIM vent hose.
9. Connect the AIR  supply tip (clear hose) to the adapter.
10. Press the remote button to activate AIR flow. 
    NOTE:

    Depending on the vehicles fuel level, or vehicle venting configuration, it can take several minutes to fill the system.

11. Compare the flow meter indicator ball reading to the red flag.
    NOTE:

    If the indicator ball drops down to the bottom of the air flow meter, or below the red flag that would indicate that the system is sealed and not leaking.

    Select the appropriate response from the list below:

    The ball drops down to the bottom of the air flow meter, or below the red flag; 

    • This indicates that the leak is coming from the vent valves inside the ESIM since the rest of the system is not leaking. Replace the ESIM in accordance with the Service Information.
    • Perform the Intrusive Leak Evaluation again to verify repair.

    The ball stays above the red flag indicating a leak in the system; 

    • This indicates that the leak is not coming from vent valves inside the ESIM. There is a leak elsewhere in the system. Leak test the system to find and repair the leak using one of the following methods; 
    • Smoke test:  Attach the black hose to the adaptor and switch the EELD tester to smoke. Pressurize the system with smoke from the EELD tester and look for smoke coming from around all connections and sealing points in the system. Repair or replace the leaking component.
    • Hydrocarbon Sniffer:  Continue pressurizing the system and check for a leak using the TIF8800X - Combustible Gas Detector or equivalent around all connections and sealing points in the system. Repair or replace the leaking component.
    • Bubble test:  Continue pressurizing the system and check for a leak by applying Mopar Air Leak Detector or equivalent around all connections and sealing points in the system and look for bubbles indicating a leak. Repair or replace the leaking component.
    • To check the Purge Solenoid  for an internal leak, remove the Manifold Hose from the Purge Solenoid, fill the system with smoke and check for smoke coming through the Purge Solenoid. If smoke is present, replace the Purge Solenoid in accordance with the Service Information.
    • Perform the Intrusive Leak Evaluation again to verify repair. 

1. Remove the Canister Tube (that connects to the Fuel Tank on the other end) from the Charcoal Canister.
2. Attach a hand vacuum pump to the fitting on the canister.
   NOTE:

   A small clamp or zip tie can be used to make sure the plug is tightly secured and not leaking.

3. Pump the hand vacuum pump until the ESIM Switch closes.
   NOTE:

   This should only take a few pumps.

4. With the scan tool, monitor the ESIM Switch state for up to 10 minutes.
   NOTE:

   This checks for leaks on the fresh air side of system (ESIM internal valves and seal, Charcoal Canister, Purge Solenoid and Purge Tube between the solenoid and canister). The ESIM Switch should remain closed since pressure from the fuel tank vapors are no longer acting on the canister and switch assuming no or minimal temperature change.

   Did the ESIM Switch remain closed for a minimum of 5 minutes?

   Yes 

   • The leak is on the Fuel Tank side of the system. Go To  7

   No 

   • The leak is on the fresh air (canister) side of the system. Go To  8

1. To continue testing you will need the (special tool #8404C, Kit, EELD And Accessory)
2. Connect the red power lead of the EELD to the Battery positive terminal and the black ground lead to Battery negative terminal.
3. Connect shop air to the EELD.
4. Set the smoke/air control switch to Smoke  .
5. Attach the black hose to the Canister Tube.
6. Press the remote button to fill the Fuel Tank side of the system with smoke.

   Leak test the system to find and repair the leak using one of the following methods: 

   • Smoke test:  Attach the black hose to the adaptor and switch the EELD tester to smoke. Pressurize the system with smoke from the EELD tester and look for smoke coming from around all connections and sealing points in the system. Repair or replace the leaking component.
   • Hydrocarbon Sniffer:  Continue pressurizing the system and check for a leak using the TIF8800X - Combustible Gas Detector or equivalent around all connections and sealing points in the system. Repair or replace the leaking component.
   • Bubble test:  Continue pressurizing the system and check for a leak by applying Mopar Air Leak Detector or equivalent around all connections and sealing points in the system and look for bubbles indicating a leak. Repair or replace the leaking component.
   • To check the Purge Solenoid  for an internal leak, remove the Manifold Hose from the Purge Solenoid, fill the system with smoke and check for smoke coming through the Purge Solenoid. If smoke is present, replace the Purge Solenoid in accordance with the Service Information.
   • Perform the Intrusive Leak Evaluation again to verify repair. 

1. To continue testing you will need the (special tool #8404C, Kit, EELD And Accessory)
2. Connect the red power lead of the EELD to the Battery positive terminal and the black ground lead to Battery negative terminal.
3. Connect shop air to the EELD.
4. Set the smoke/air control switch to AIR  to pressurize the system.
5. Press the remote smoke/air start button.
6. Block off the end of the tester's AIR supply tip (clear hose) while pressing the remote 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.

7. If the indicator ball is not resting on the bottom of air flow meter, position the red flag on the air flow meter so it is aligned with ball.
8. Connect the service adapter (special tool #8404-ADP, Smoke Machine Adapters) to the ESIM vent hose.
9. Connect the AIR  supply tip (clear hose) to the adapter.
10. Press the remote button to activate AIR flow. 
11. Compare the flow meter indicator ball reading to the red flag.

    Select the appropriate response from the list below:

    The ball drops down to the bottom of the air flow meter, or below the red flag; 

    • This indicates that the leak is coming from the vent valves inside the ESIM. Replace the ESIM in accordance with the Service Information.

    The ball stays above the red flag indicating a leak in the system; 

    • This indicates that the leak is not coming from vent valves inside the ESIM. There is a leak elsewhere in the system. Leak test the system to find and repair the leak using one of the following methods; 
    • Smoke test:  Attach the black hose to the adaptor and switch the EELD tester to smoke. Pressurize the system with smoke from the EELD tester and look for smoke coming from around all connections and sealing points in the system. Repair or replace the leaking component.
    • Hydrocarbon Sniffer:  Continue pressurizing the system and check for a leak using the TIF8800X - Combustible Gas Detector or equivalent around all connections and sealing points in the system. Repair or replace the leaking component.
    • Bubble test:  Continue pressurizing the system and check for a leak by applying Mopar Air Leak Detector or equivalent around all connections and sealing points in the system and look for bubbles indicating a leak. Repair or replace the leaking component.
    • To check the Purge Solenoid  for an internal leak, remove the Manifold Hose from the Purge Solenoid, fill the system with smoke and check for smoke coming through the Purge Solenoid. If smoke is present, replace the Purge Solenoid in accordance with the Service Information.
    • Perform the Intrusive Leak Evaluation again to verify repair.