Dtc P1271 Fuel Regulator Circuit Malfunction (Edu Drive)

DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

WIRING DIAGRAM

INSPECTION PROCEDURE

READ OUTPUT DTC

INSPECT PRESSURE DISCHARGE VALVE

CHECK WIRE HARNESS (EDU - PRESSURE DISCHARGE VALVE)

CHECK WIRE HARNESS (EDU - ECM)

CHECK EDU (POWER SOURCE CIRCUIT)

REPLACE EDU

CHECK WHETHER DTC OUTPUT RECURS

REPLACE COMMON RAIL ASSEMBLY

DESCRIPTION

УКАЗАНИЕ:

1. For more information on the pressure discharge valve and the common rail system, refer to the following procedures (see page RAV4_ACA30 RM000000XSN006X.html).
   
2. For more information on the EDU, refer to the following procedures (see page RAV4_ACA30 RM000000XSN006X.html).
   
3. If P1271 and/or P1272 is present, refer to the DTC chart for the fuel system (see page RAV4_ACA30 RM000000XSN006X.html).
   

УКАЗАНИЕ:

1. After confirming DTC P1271 and/or P1272, check the fuel pressure inside the common rail in the "Powertrain / Engine and ECT / Data List / Fuel Press" menu using the intelligent tester.
   
2. P1271:
   After clearing the DTC, drive the vehicle at 50 km/h (31 mph) with the third gear and then decelerate by releasing the accelerator pedal. Check that P1271 is not present.
   
3. P1272:
   After clearing the DTC, start and stop the engine twice, and then confirm that P1272 is not present.
   

MONITOR DESCRIPTION

1. P1271 (Open or short in pressure discharge valve circuit):
   This DTC will be set if there is no valve opening confirmation (IJf) signal sent from the EDU to the ECM, if the ECM has commanded the EDU to open the pressure discharge valve. This DTC refers to an open or short circuit malfunction of the pressure discharge valve circuit, not a malfunction that includes a valve that is stuck open or closed.
   The EDU monitors the current supplied to the pressure discharge valve to verify that the current flows into the valve. If the current exceeds the specified level, the EDU interprets this as the IJf signal is low. If this DTC is present, the ECM enters the fail-safe mode and limits engine power. The fail-safe mode continues until the ignition switch is turned off.
   
   
   
   
   

1. P1272 (Closed malfunction of the pressure discharge valve):
   The pressure discharge valve will open and discharge the internal fuel pressure from the common rail to the fuel tank when the ignition switch is turned off. In this event, the ECM compares the actual drop rate of the internal fuel pressure and the target drop rate. If the ECM judges the actual drop rate is smaller than the target, the ECM then judges that the valve is stuck closed and sets this DTC. This DTC will be stored if the internal fuel pressure does not drop to the target after the ignition switch has been turned off.
   If this DTC is present, the ECM enters a fail-safe mode and limits engine power. The fail-safe mode continues until the ignition switch is turned off.
   

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

WIRING DIAGRAM

INSPECTION PROCEDURE

ПРИМЕЧАНИЕ:

After replacing the ECM, the new ECM needs registration (see page RAV4_ACA30 RM000000TJ4007X.html) and initialization (see page RAV4_ACA30 RM000000TIN007X.html).

УКАЗАНИЕ:

1. After completing repairs, confirm that P1271 and/or P1272 does not recur.
   
2. If P0200 and P1271 are present simultaneously, there is an open in the INJF wire harness between the EDU and ECM, or there is an open in the wire harness for both injector and pressure discharge valve.
   

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch on (IG) and turn the tester ON.
   

3. Enter the following menus: Powertrain / Engine and ECT / DTC.
   

4. Read DTCs.
   

   Result:

   Display (DTC Output)	Proceed to
   P1271 and/or P1272	A
   P1272	B

1. Disconnect the B59 pressure discharge valve connector.
   

2. Measure the resistance of the terminals of the pressure discharge valve.
   

   Standard resistance:

   Tester Connection	Condition	Specified Condition
   B59-1 - B59-2	20°C (68°F)	0.85 to 1.05 Ω

3. Reconnect the pressure discharge valve connector.
   

1. Disconnect the B58 EDU connector.
   

2. Disconnect the B59 pressure discharge valve connector.
   

3. Measure the resistance of the wire harness side connectors.
   

   Standard resistance:

   Tester Connection	Specified Condition
   B58-3 (RLF+) - B59-2	Below 1 Ω
   B58-6 (RLF-) - B59-1	Below 1 Ω
   B58-3 (RLF+) or B59-2 - Body ground	10 kΩ or higher
   B58-6 (RLF-) or B59-1 - Body ground	10 kΩ or higher

4. Reconnect the EDU connector.
   

5. Reconnect the pressure discharge valve connector.
   

1. Disconnect the B51 EDU connector.
   

2. Disconnect the B32 ECM connector.
   

3. Measure the resistance of the wire harness side connectors.
   

   Standard resistance:

   Tester Connection	Specified Condition
   B51-7 (PRD) - B32-52 (PRD)	Below 1 Ω
   B51-7 (PRD) or B32-52 (PRD) - Body ground	10 kΩ or higher

4. Reconnect the EDU connector.
   

5. Reconnect the ECM connector.
   

1. Disconnect the B50 EDU connector.
   

2. Turn the ignition switch on (IG).
   

3. Measure the voltage of the specified terminals of each EDU wire harness side connector.
   

   Standard voltage:

   Tester Connection	Specified Condition
   B50-3 (+B) - B50-2 (GND)	9 to 14 V

4. Reconnect the EDU connector.
   

1. Replace the EDU (see page RAV4_ACA30 RM0000015C2002X.html).
   

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch on (IG) and turn the tester ON.
   

3. Clear DTCs (see page RAV4_ACA30 RM000000PDK01FX.html).
   

4. Start the engine and drive the vehicle for approximately 15 minutes.
   

5. Enter the following menus: Powertrain / Engine and ECT / DTC.
   

6. Read the DTCs.
   

   Result:

   Display (DTC Output)	Proceed to
   P1271 and/or P1272	A
   No output	B

1. Replace the common rail assembly (see page RAV4_ACA30 RM000001IKR002X.html).