DTC SUMMARY |
DTC No. | Monitoring Item |
Malfunction Detection Condition |
Trouble Area | Detection Timing |
Detection Logic | |
P0455 | EVAP gross leak |
Leak
detection pump creates negative pressure (vacuum) in EVAP system and
EVAP system pressure measured. Reference pressure measured at start and
at end of leak check. If stabilized pressure higher than [second reference pressure x 0.2], ECM determines that EVAP system has large leak. |
- Fuel tank cap (loose)
- Leak from EVAP line
(Canister - Fuel tank)
- Leak from EVAP line
(Purge VSV - Canister)
- Canister pump module
- Leak from fuel tank
- Leak from canister
| While ignition switch off |
2 trip | | P0456 |
EVAP small leak | Leak
detection pump creates negative pressure (vacuum) in EVAP system and
EVAP system pressure measured. Reference pressure measured at start and
at end of leak check. If stabilized pressure higher than second reference pressure, ECM determines that EVAP system has small leak. |
- Fuel tank cap (loose)
- Leak from EVAP line
(Canister - Fuel tank)
- Leak from EVAP line
(Purge VSV - Canister)
- Canister pump module
- Leak from fuel tank
- Leak from canister
| While ignition switch off |
2 trip | 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 35°C (95°F) 5 hours
after the ignition switch is turned off, the monitor check starts 2
hours later. If it is still not below 35°C (95°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.
- (a) P0455: EVAP gross leak
In operation C, the leak detection pump creates
negative pressure (vacuum) in the EVAP system and the EVAP system
pressure is measured. If the stabilized system pressure is higher than
[second reference pressure x 0.2] (near atmospheric pressure), the ECM
determines that the EVAP system has a large leak, illuminates the MIL
and stores the DTC (2 trip detection logic).
- (b) P0456: EVAP very small leak
In operation C, the leak detection pump creates
negative pressure (vacuum) in the EVAP system and the EVAP system
pressure is measured. If the stabilized system pressure is higher than
the second reference pressure, the ECM determines that the EVAP system
has a small leak, illuminates the MIL and stores the DTC (2 trip
detection logic). 
MONITOR STRATEGY |
Required Sensors/Components | Purge VSV and canister pump module | |
Frequency of Operation | Once per driving cycle | |
Duration | Within 20 minutes (varies with amount of fuel in tank): P0455 (Pattern 1) and P0456
Within 15 minutes (varies with amount of fuel in tank): P0455 (Pattern 2) | |
MIL Operation | 2 driving cycles | |
Sequence of Operation | None | TYPICAL ENABLING CONDITIONS |
Monitor runs whenever following DTCs not present |
P0452, P0453 (EVAP system) | P0455 (Pattern 1), P0456 |
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) | P0455 (Pattern 2) |
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 | |
Purge VSV | Not operated by scan tool | |
Vent valve | Not operated by scan tool | |
Leak detection pump | Not operated by scan tool | |
Both of the following conditions 1 and 2 met before key off |
- | | 1. Duration that vehicle has been driven |
5 minutes or more | | 2. EVAP purge operation |
Performed | | ECT | 4.4 to 40°C (40 to 104°F) | |
IAT | 4.4 to 40°C (40 to 104°F) | TYPICAL MALFUNCTION THRESHOLDS P0455 (Gross leak) |
EVAP pressure when vacuum introduction complete | Higher than reference pressure x 0.2 | P0456 (Small leak) |
EVAP pressure when vacuum introduction complete | Between reference pressure and reference pressure x 0.2 | 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 the Techstream. It takes a maximum of
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.
- Enter the following menus: 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: P0455 or P0456.
- Check the DTC judgment result.
|
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
).
| NEXT |  |
END | |
