M20C-FKS ENGINE CONTROL SFI SYSTEM P044312 EVAP System Purge Control Valve "A" Circuit Circuit Short to Battery P044314 EVAP System Purge Control Valve "A" Circuit Circuit Short to Ground or Open
DESCRIPTION
To reduce hydrocarbon (HC) emissions, evaporated fuel from the fuel tank is routed through a charcoal canister to the intake manifold for combustion in the cylinders.
The ECM changes the duty signals to the purge VSV (Vacuum Switching Valve for Purge Control) so that the intake amount of hydrocarbon (HC) emissions is appropriate for the driving conditions (engine load, engine speed, vehicle speed, etc.) after the engine is warmed up.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory | Note |
|---|---|---|---|---|---|---|
| P044312 | EVAP System Purge Control Valve "A" Circuit Circuit Short to Battery | Both of the following conditions (a) and (b) are met (1 trip detection logic):
(a) The purge VSV operation duty signal is 5% or more. (b) Short in purge VSV circuit and power supply circuit for 10 seconds or more. |
·
Short in purge VSV circuit ·
Purge VSV ·
ECM |
Comes on | DTC stored | SAE: P0459 |
| P044314 | EVAP System Purge Control Valve "A" Circuit Circuit Short to Ground or Open | Both of the following conditions (a) and (b) are met (1 trip detection logic):
(a) The purge VSV operation duty signal is 95% or less. (b) Open or short to ground in purge VSV circuit for 10 seconds or more. |
·
Open or short in purge VSV circuit ·
Purge VSV ·
ECM |
Comes on | DTC stored | SAE: P0458 |
MONITOR DESCRIPTION
The ECM monitors the output voltage while the purge VSV is operating.
The purge VSV turns on and off according to ON/OFF switching of a transistor inside the ECM.
If the ECM detects a short to +B in the purge VSV circuit when the purge VSV is operating, the ECM determines there is a malfunction in the purge VSV circuit and stores a DTC P044312.
If the ECM detects an open or short to ground in the purge VSV circuit when the purge VSV is not operating, the ECM determines there is a malfunction in the purge VSV circuit and stores a DTC P044314.
MONITOR STRATEGY
| Frequency of Operation | Continuous |
CONFIRMATION DRIVING PATTERN
- HINT:
- ·
After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
·When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON and turn the GTS on.
Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher [A].
- HINT:
-
The A/C switch and all accessory switches should be off.
Idle the engine for 15 minutes or more [B].
- HINT:
-
Check the EVAP (Purge) VSV item in the Data List. When the value of this item is between 5 and 95%, the judgment will be performed.
Enter the following menus: Powertrain / Engine / Trouble Codes [C].
Read the pending DTCs.
- HINT:
- ·
If a pending DTC is output, the system is malfunctioning.
·If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Input the DTC: P044312 or P044314.
Check the DTC judgment result.
| GTS 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 |
- HINT:
- ·
If the judgment result shows NORMAL, the system is normal.
·If the judgment result shows ABNORMAL, the system has a malfunction.
·If the judgment result shows INCOMPLETE, perform steps [D] and [E].
·[A] to [C]: Normal judgment procedure.
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
·When clearing the permanent DTCs, do not disconnect the cable from the battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
Drive the vehicle at a constant speed between 40 and 60 km/h (25 and 37 mph) for 10 minutes or more [D].
- CAUTION:
-
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
Enter the following menus: Powertrain / Engine / Trouble Codes [E].
Read the pending DTCs.
- HINT:
- ·
If a pending DTC is output, the system is malfunctioning.
·If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Input the DTC: P044312 or P044314.
Check the DTC judgment result.
| GTS 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 |
- HINT:
- ·
If the judgment result shows NORMAL, the system is normal.
·If the judgment result shows ABNORMAL, the system has a malfunction.
·If the judgment result shows INCOMPLETE, perform the Confirmation Driving Pattern and check the DTC judgment result again.
·[A] to [E]: Normal judgment procedure.
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
·When clearing the permanent DTCs, do not disconnect the cable from the battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
- NOTICE:
-
Inspect the fuses of circuits related to this system before performing the following procedure.
- HINT:
-
Read Freeze Frame Data using the GTS. The ECM records vehicle and driving condition information as Freeze Frame Data the moment a DTC is stored. When troubleshooting, Freeze Frame Data can help determine if the vehicle was moving or stationary, 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.
PROCEDURE
| *a | VSV is on |
| *b | VSV is off |
Connect the GTS to the DLC3.
Disconnect the fuel vapor feed hose (on the canister side) from the purge VSV.
Turn the ignition switch to ON.
Turn the GTS on.
Start the engine.
Enter the following menus: Powertrain / Engine / Active Test / Activate the EVAP Purge VSV.
- Powertrain > Engine > Active Test
-
Tester Display Activate the EVAP Purge VSV - 50004 372 1
When the purge VSV is operated using the GTS, check whether the port of the purge VSV applies suction to your finger.
- OK:
GTS Operation Specified Condition ON Purge VSV port applies suction to finger OFF Purge VSV port applies no suction to finger
- HINT:
-
Jiggle the wire harness and connector to increase the likelihood of detecting malfunctions that do not always occur.
- Result:
Proceed to OK NG
OK
NG
Inspect the purge VSV.
- Result:
Proceed to OK NG
OK
NG
| *a | Front view of wire harness connector
(to Purge VSV) |
Disconnect the purge VSV connector.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
Tester Connection Switch Condition Specified Condition C19-1 - Body ground Ignition switch ON 11 to 14 V
- Result:
Proceed to OK NG
OK
NG
Disconnect the purge VSV connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition C19-2 - C71-102 (PRG) Always Below 1 Ω C19-2 or C71-102 (PRG) - Body ground and other terminals Always 10 kΩ or higher
- Result:
Proceed to OK NG
OK
NG