P2419
DTC P2419 Evaporative Emission System Switching Valve Control Circuit LowDTC P2420 Evaporative Emission System Switching Valve Control Circuit High
DESCRIPTION
Malfunction Condition:
While the engine is running, if a predetermined condition (closed-loop, etc.) is met, the Purge VSV is opened by the ECM and stored fuel vapors in the canister are purged to the intake manifold. The ECM changes the duty cycle ratio of the purge VSV to control purge flow volume.
The purge flow volume is also determined by the intake manifold pressure. Atmospheric pressure is allowed into the canister through the vent valve to ensure that the purge flow is maintained when the negative pressure (vacuum) is applied to the canister.
The following 2 monitors run to confirm appropriate EVAP system operation.
1. Key-off monitor
This monitor checks for Evaporative Emission (EVAP) system leaks and canister pump module malfunctions. The monitor starts 5 hours (± 15 minutes) after the ignition switch is turned OFF. 5 hours are required to allow enough time for the fuel to cool down to stabilize the Fuel Tank Pressure (FTP), thus making the EVAP system monitor more accurate.
The leak detection pump creates negative pressure (vacuum) in the EVAP system and the pressure is measured. Finally, the ECM monitors for leaks from the EVAP system and malfunctions in both the canister pump module and purge VSV, based on the EVAP pressure.
2. Purge flow monitor
The purge flow monitor consists of the 2 monitors. The 1st monitor is always conducted every time and the 2nd monitor is conducted if necessary.
- The 1st monitor
While the engine is running and the purge VSV is ON (open), the ECM monitors the purge flow by measuring the EVAP pressure change. If negative pressure is not created, the ECM begins the 2nd monitor.
- The 2nd monitor
The vent valve is turned OFF (open) and the EVAP pressure is then measured. If the variation in the pressure is less than 0.5 kPa (3.75 mmHg), the ECM interprets this as the purge VSV being stuck closed, and illuminates the MIL and sets DTC P0441 (2 trip detection logic).
Atmospheric pressure check:
In order to ensure reliable malfunction detection, the variation between the atmospheric pressures, before and after conduction of the purge flow monitor, is measured by the ECM.
Wiring Diagram:
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INSPECTION PROCEDURE
NOTE: The intelligent tester is required to conduct the following diagnostic troubleshooting procedure.
HINT:
- Using the intelligent tester monitor results enable the EVAP (Evaporative Emission) system to be confirmed.
- Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
MONITOR DESCRIPTION
5 hours* after the ignition switch is turned OFF, the leak detection pump creates negative pressure (vacuum) in the EVAP (Evaporative Emission) system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure.
HINT: *: If the engine coolant temperature is not below 35 degrees C (95 degrees F) 5 hours after the ignition switch is turned OFF, the monitor check starts 2 hours later. If it is still not below 35 degrees C (95 degrees F) 7 hours after the ignition switch is turned OFF, the monitor check starts 2.5 hours later.
1. P2419: Vent valve stuck ON (Closed)
In sequence B, to determine the leak criterion, the leak detection pump creates negative pressure in the canister pump module through the reference orifice. If the pressure is out of specified range or is not saturated, the ECM illuminates the MIL and sets DTCs P043E, P043F, P2401, P2402 and P2419 (2-trip detection logic).
2. P2420: Vent valve stuck OFF (Vent)
After sequence B, the ECM changes the vent value from OFF (Vent) to ON (Closed) and measures the EVAP pressure. If the pressure does not change, the ECM illuminates the MIL and sets DTC P2420 (2-trip detection logic).
Monitor Strategy:
Typical Enabling Conditions (Part 1):
Typical Enabling Conditions (Part 2):
Typical Malfunction Thresholds:
OBD II MONITOR SPECIFICATIONS
MONITOR RESULT
The monitor result (mode 06) allows the OBD II scan tool to display the monitor status, test value and test limit.
A problem in the EVAP system can be found by comparing the test value and test limit. This procedure is described in "CHECKING MONITOR STATUS".
Check the monitor result after running the vehicle with monitor drive pattern (Refer to "MONITOR CONFIRMATION DRIVE PATTERN").
- TID (Test Identification) is assigned to each emission-related component.
- TLT (Test Limit Type):
If TLT is 0, the component is malfunctioning when the test value is higher than the test limit.
If TLT is 1, the component is malfunctioning when the test value is lower than the test limit.
- CID (Component Identification) is assigned to each test value.
- Unit Conversion is used to calculate the test value indicated on generic OBD scan tools.