DTC SUMMARY
DTC No. | Monitoring Item |
Malfunction Detection Condition |
Trouble Area | Detection Timing |
Detection Logic |
P2420 | Vent valve stuck open (vent) |
Following condition met during key-off EVAP monitor:
- EVAP pressure change when vent valve closed (ON) less than 0.3 kPa-g (2.25 mmHg-g)
|
- Canister pump module (Reference orifice, leak detection pump, vent valve)
- Connector/wire harness (Canister pump module - ECM)
- ECM
| While ignition switch off |
2 trip | HINT: The vent valve is built into the canister pump module. DESCRIPTION
The description can be found in the EVAP (Evaporative Emission) System (See page
). CAUTION / NOTICE / HINT
Refer to the EVAP System (See page
). MONITOR DESCRIPTION
5
hours* after the ignition switch is turned off, the leak detection pump
creates negative pressure (vacuum) in the EVAP system. The ECM monitors
for leaks and actuator malfunctions based on the EVAP pressure. HINT:
*:
If the engine coolant temperature is not below 37.5°C (99.5°F) 5 hours
after the ignition switch is turned off, the monitor check starts 2
hours later. If it is still not below 37.5°C (99.5°F) 7 hours after the
ignition switch is turned off, the monitor check starts 2.5 hours later.
Sequence | Operation |
Description | Duration |
- | ECM activation |
Activated by soak timer 5, 7 or 9.5 hours after ignition switch turned off. |
- | A |
Atmospheric pressure measurement | Vent valve turned OFF (vent) and EVAP system pressure measured by ECM in order to register atmospheric pressure.
If pressure in EVAP system not between 70 kPa-a and 110 kPa-a (525 mmHg-a and 825 mmHg-a), ECM cancels EVAP system monitor. |
60 seconds |
B | First reference pressure measurement |
In
order to determine reference pressure, leak detection pump creates
negative pressure (vacuum) through reference orifice and then ECM checks
if leak detection pump and vent valve operate normally. |
360 seconds |
C | EVAP system pressure measurement |
Vent valve turned ON (closed) to shut EVAP system. Negative pressure (vacuum) created in EVAP system, and EVAP system pressure then measured.
Write down measured value as it will be used in leak check. If EVAP pressure does not stabilize within 15 minutes, ECM cancels EVAP system monitor. |
15 minutes* |
D | Purge VSV monitor |
Purge VSV opened and then EVAP system pressure measured by ECM.
Large increase indicates normality. |
10 seconds |
E | Second reference pressure measurement |
After second reference pressure measurement, leak check performed by comparing first and second reference pressure.
If stabilized system pressure higher than second reference pressure, ECM determines that EVAP system leaking. |
60 seconds |
- | Final check |
Atmospheric pressure measured and then monitoring result recorded by ECM. |
- | *: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.
P2420: Vent valve stuck open (vent)
In
operation C, the vent valve turns ON (closes) and the EVAP system
pressure is then measured by the ECM using the canister pressure sensor
to conduct an EVAP leak check. If the pressure does not increase when
the vent valve is open, the ECM interprets this as the vent valve being
stuck open. The ECM illuminates the MIL and stores the DTC.
MONITOR STRATEGY
Required Sensors/Components | Purge VSV and canister pump module |
Frequency of Operation | Once per driving cycle |
Duration | Within 7 minutes (varies with amount of fuel in tank) |
MIL Operation | 2 driving cycles |
Sequence of Operation | None | TYPICAL ENABLING CONDITIONS
Monitor runs whenever following DTCs not present |
P0452, P0453 (EVAP system) | EVAP key-off monitor runs when all of following conditions met |
- | Atmospheric pressure |
70 to 110 kPa-a (525 to 825 mmHg-a) |
Battery voltage | 10.5 V or more |
Vehicle speed | Below 4 km/h (2.5 mph) |
Ignition switch | Off |
Time after key off | 5, 7 or 9.5 hours |
Purge VSV | Not operated by scan tool |
Vent valve | Not operated by scan tool |
Leak detection pump | Not operated by scan tool |
Both of following conditions met before key off |
Conditions 1 and 2 | 1. Duration that vehicle driven |
5 minutes or more | 2. EVAP purge operation |
Performed | ECT |
4.4 to 35°C (40 to 95°F) |
IAT | 4.4 to 35°C (40 to 95°F) | TYPICAL MALFUNCTION THRESHOLDS
EVAP pressure change after EVAP canister vent valve ON | Less than 0.3 kPa-g (2.25 mmHg-g) | MONITOR RESULT
Refer to Checking Monitor Status (See page ). CONFIRMATION DRIVING PATTERN
NOTICE:
- The Evaporative System Check (Automatic Mode) consists of 6 steps
performed automatically by Techstream. It takes a maximum of the
approximately 24 minutes.
- Do not perform the Evaporative System Check when the fuel tank is more
than 90% full because the cut-off valve may be closed, making the fuel
tank leak check unavailable.
- Do not run the engine during this operation.
- When the temperature of the fuel is 35°C (95°F) or higher, a large
amount of vapor forms and any check results become inaccurate. When
performing the Evaporative System Check, keep the fuel temperature below
35°C (95°F).
- Connect the Techstream to the DLC3.
- Turn the ignition switch to ON and turn the Techstream on.
- Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).
- Turn the ignition switch off and wait for at least 30 seconds.
- Turn the ignition switch to ON and turn the Techstream on [A].
- Enter the following menu items: Powertrain / Engine and ECT / Utility / Evaporative System Check / Automatic Mode.
- After the "Evaporative System Check" is completed, check All Readiness
by entering the following menus: Powertrain / Engine and ECT / Utility /
All Readiness.
- Input the DTC: P2420.
- Check the DTC judgment result [B].
Tester Display |
Description |
NORMAL |
- DTC judgment completed
- System normal
|
ABNORMAL |
- DTC judgment completed
- System abnormal
|
INCOMPLETE |
- DTC judgment not completed
- Perform driving pattern after confirming DTC enabling conditions
|
N/A |
- Unable to perform DTC judgment
- Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
|
HINT:
If the judgment result shows ABNORMAL, the system has a malfunction.
- If the test result is INCOMPLETE or N/A and no pending DTC is output,
perform a universal trip and check for permanent DTCs (See page
).
HINT:
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
PROCEDURE
(a) Refer to EVAP System (See page
).
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END | |