Diagnostic Procedure
- Check for any related TSBs before continuing.NOTE: If any of the following DTCs are set (P0443, P0452, P0453, P0498 or P0499) diagnose them first before continuing with P0440.
Ignition on, engine not running.
With the DRBIII®, read DTCs and record the related Freeze Frame data.
Is the Good Trip Counter displayed and equal to zero?
- Yes --> Go To 2
- No --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure).
- Turn the ignition off.
Perform a visual and physical inspection of the entire Evaporative Emission system. Check for the following conditions:
- Hoses disconnected or left off
- Holes or cracks
- Loose seal points
- Evidence of damaged components
- Incorrect routing of hoses and tubes
- Fuel Cap left off or bad gasket seal
Were any of the above conditions found?
- Yes --> Repair as necessary.
- No --> Go To 3
- Carefully inspect the Evap Purge Solenoid vacuum supply hose for proper routing. Check for a pinched or plugged hose from the throttle body to the Purge Solenoid. Ensure the vacuum port at the throttle body is free from any blockage. Were any problems found?
- Yes --> Repair the vacuum supply, hose/tube as necessary.
- No --> Go To 4
- Disconnect the vacuum supply hoses form the EVAP Purge Solenoid.
Using a hand vacuum pump, apply 10 in Hg to the "CAN" side of the EVAP Purge Solenoid.
Ignition on, engine not running.
Observe the vacuum gauge.
With the DRBIII®, actuate the EVAP Purge Solenoid.
Does the vacuum drop when the solenoid is actuated?
- Yes --> Go To 5
- No --> Replace the Evap Purge Solenoid
- Connect the previously disconnected vacuum hose.
Start the engine.
Allow the engine to idle.
Using the DRBIII®, perform the NVLD FORCED MONITOR TEST.
Monitor the NVLD Switch state.
NOTE: As the test runs, the NVLD Switch should go from an OPEN state to a CLOSED state and then return to OPEN when the test is complete.Did the NVLD Switch operate as described above?
- Yes --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure).
- No --> Go To 6
- To continue testing you will need Miller Tool #8404 Evaporative Emission Leak Detector (EELD).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.NOTE: The fuel tank should have between 20% and 80% of fuel tank capacity to properly test the Evap system.
Connect the red power lead of EELD to the battery positive terminal and the black ground lead to battery negative terminal.
NOTE: See Charts and Graph support material EELD Calibration Setup for an example.Block the vent hose of the EVAP Canister.
Connect shop air to the EELD.
Set the smoke/air control switch to AIR.
Insert the tester's AIR supply tip (clear hose) into the.040 orifice on the tester's control panel.
Press the remote smoke/air start button.
Position the red flag on the air flow meter so it is aligned with the indicator ball.
When the calibration is complete, release the remote button. The EELD flow meter is now calibrated in liters per minute.
Install the service port adapter #8404-14 on the vehicle's service port (if equipped) or install the #8404-ADP into the filter line.
Connect the Air supply hose from the EELD to the service port (if equipped) or to the #8404-ADP adapter.
Press the remote button to activate AIR flow.
NOTE: Larger volume fuel tanks, lower fuel levels or if the vehicle is equipped with a Flow Management Valve, this may indicate high flow and will require 4 to 5 minutes to fill.Compare the flow meter indicator ball reading to the red flag.
ABOVE the red flag indicates a leak present.
BELOW the red flag indicates a sealed system.
Is the indicator ball above the red flag?
- Yes --> Go To 7
- No --> Go To 8
- To continue testing, you will need Miller Tool #8404 Evaporative Emissions Leak Detector (EELD).
Remove the Air supply hose from the service port or the #8404-ADP adapter.
Connect the SMOKE supply tip (black hose) to the service port (if equipped) or to the #8404-ADP adapter.
Set the smoke/air control switch to SMOKE.
Press the remote smoke/air start button.
While still holding the remote smoke/air start button, use the white light (#8404-CLL) to follow the EVAP system path, and look for the source of the leak indicated by exiting smoke.
If a leak is concealed from view (i.e., top of fuel tank), release the remote smoke/air start button, and use the ultraviolet (UV) black light #8404-UVL and the yellow goggles 8404-20 to look for residual traces of dye that are left behind by the smoke. The exiting smoke deposits a residual fluid that is either bright green or bright yellow in color when viewed with a UV light.
Was a leak found?
- Yes --> Repair or replace the leaking component as necessary.
- No --> Go To 11
- Turn the ignition off.
Disconnect the NVLD electrical harness connector.
Check connectors - Clean/repair as necessary.
Ignition on, engine not running.
Connect a jumper wire between the (K107) NVLD Switch Signal circuit and the (Z910) Ground circuit in the NVLD electrical harness connector.
Monitor the NVLD Switch state on the DRBIII®.
Does the Switch change from OPEN to CLOSED.
- Yes --> Replace the NVLD Assembly.
- No --> Go To 9
NOTE: Remove the jumper wire before continuing. - Turn the ignition off.
Measure the resistance between the (Z910) Ground circuit and ground.
Is the resistance below 5.0 ohms?
- Yes --> Go To 10
- No --> Repair the open in the (Z910) Ground circuit.
- Disconnect the PCM harness connectors.CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMINALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Measure the resistance of the (K107) NVLD Switch Signal circuit from the NVLD electrical harness connector to the appropriate terminal of the special tool #8815. Is the resistance below 5.0 ohms?
- Yes --> Go To 11
- No --> Repair the open in the (K107) Signal circuit.
- Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.
If there are no possible causes remaining, view repair.
- Repair
- Replace and program the Powertrain Control Module per Service Information.
- Perform (NGC) POWERTRAIN VERIFICATION TEST VER - 6 .
- Repair