DTC P145F
DTC P145F: Evaporative Emission (EVAP) Leak Check Module Pressure Sensor Range/Performance Problem
General Description
The powertrain control module (PCM) starts the evaporative emission (EVAP) system diagnosis after the vehicle has been turned to the OFF (LOCK) mode, and has met all other enable conditions (initial engine coolant temperature [ECT Sensor 1] and off for at least 5 hours). The EVAP system diagnosis is performed by reducing pressure between the EVAP canister and the atmosphere.
A malfunction is detected and a DTC is stored when the max and min values of the pressure measurements within the prescribed time during reference pressure measurement is equal to or more than the prescribed value.
EVAP leak check module operation flow
- Reference pressure measurement: Malfunction detection in the EVAP leak check module and determination of early completion of pressure reduction when normal.
- System pressure reduction: Pressure in the EVAP system is reduced to measure the ultimate pressure.
- Reference pressure re-measurement: Leak is detected by comparing with the ultimate pressure of the system pressure reduction.
- Reference value is to be measured twice considering change in the characteristics of the EVAP leak check module vacuum pump during detection.
Reference pressure is the pressure reduction caused by the reference orifice (#40 equivalent) in the EVAP leak check module used to check for leak by comparison with the system pressure reduction.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Once per driving cycle |
| Sequence | None |
| Duration | At least 6 minutes 10 seconds but not more than 18 minutes 45 seconds |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Elapsed time after the vehicle condition is turned to the READY TO DRIVE mode | 10 minutes | - |
| Elapsed time after the vehicle condition is turned to the OFF (LOCK) mode | 5 hours | - |
| PCM wake up engine coolant temperature [ECT SENSOR 2] | 40 deg.F (5 deg.C) | 95 deg.F (35 deg.C) |
| Barometric pressure[BARO SENSOR] | 76 kPa (569 mmHg, 22.5 inHg) | - |
[ ]: HDS Parameter
| Condition | Minimum | Maximum |
|---|---|---|
| 12 volt battery voltage [BATTERY] | 10.5 V | - |
| Other | No refueling is required | |
[ ]: HDS Parameter
Malfunction Threshold
When the max and min values of the pressure measurements within the prescribed time during reference pressure measurement is 0.3 kPa (2.5 mmHg, 0.1 inHg) or more.
Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- EVAP leak check module vacuum pump failure
- Canister change over valve failure
- Reference orifice flow quantity is excessive
- Reference orifice flow quantity is too few
Confirmation Procedure
Operating Condition
- With the engine coolant temperature [ECT Sensor 2] within the specified range, turn the vehicle to the READY TO DRIVE mode, and wait for at least 10 minutes.
- Turn the vehicle to the OFF (LOCK) mode, and wait for at least 5 hours.
- PCM wake up, and wait at least 18 minutes 45 seconds.
With the HDS
Select the EVAP TEST in the Function Test Menu, then select EVAP Leak Check Module Test with the HDS.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle with the engine coolant temperature and intake air temperature at engine start-up within the specified temperature range, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle with the engine coolant temperature and intake air temperature at engine start-up within the specified temperature range, the MIL comes on and a Confirmed DTC and freeze data are stored.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool clear command or by disconnecting the 12 volt battery.