Nissan Murano: Dtc/circuit Diagnosis / P2270 Ho2s2

DTC Description

DTC DETECTION LOGIC

The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst (manifold) causes the longer switching time.

MALFUNCTION 1

To judge the malfunctions of heated oxygen sensor 2, ECM monitors whether the voltage is unusually high during various driving conditions such as fuel cut.

: 1.3 V

MALFUNCTION 2

To judge the malfunctions of heated oxygen sensor 2, ECM monitors whether the minimum voltage of sensor is sufficiently low during various driving conditions such as fuel-cut.

1. An excessively high voltage from the sensor is sent to ECM.

2. The minimum voltage from the sensor is not reached to the specified voltage.

POSSIBLE CAUSE

P2270 - 1

• Harness or connectors (The sensor circuit is open or shorted)

• Heated oxygen sensor 2

P2270 - 2

• Harness or connectors (The sensor circuit is open or shorted)

• Heated oxygen sensor 2

• Fuel pressure

• Fuel injector

FAIL-SAFE

Not applicable

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON.

3. Turn ignition switch OFF and wait at least 10 seconds.

GO TO 2.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION 1

1. Start engine and warm it up to the normal operating temperature.

2. Turn ignition switch OFF and wait at least 10 seconds.

3. Turn ignition switch ON.

4. Turn ignition switch OFF and wait at least 10 seconds.

5. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.

6. Let engine idle for 2 minutes.

7. Check 1st trip DTC.

Is 1st trip DTC detected?

Proceed to Diagnosis Procedure.

With CONSULT: GO TO 3.

Without CONSULT: GO TO 5.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION 2

NOTE:

For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30°C (32 to 86°F).

1. Select “DATA MONITOR” mode with CONSULT.

2. Start engine and warm it up to the normal operating temperature.

3. Turn ignition switch OFF and wait at least 10 seconds.

4. Turn ignition switch ON.

5. Turn ignition switch OFF and wait at least 10 seconds.

6. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.

7. Let engine idle for 1 minute.

8. Check that “COOLANT TEMP/S” indicates more than 70°C (158°F).

   If not, warm up engine and go to next step when “COOLANT TEMP/S” indication reaches 70°C (158°F).

9. Open engine hood.

10. Select “HO2S2 (B1) P1146” (for DTC P2270) of “HO2S2” in “DTC WORK SUPPORT” mode with CONSULT.

11. Follow the instruction of CONSULT display.

    NOTE:

    It will take at most 10 minutes until “COMPLETED” is displayed.

12. Touch “SELF-DIAG RESULTS”.

Which is displayed on CONSULT screen?

To check malfunction symptom before repair: Refer to Intermittent Incident.

Confirmation after repair: INSPECTION END

Proceed to Diagnosis Procedure.

GO TO 4.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION 2 AGAIN

1. Turn ignition switch OFF and leave the Nissan Murano vehicle in a cool place (soak the vehicle).

2. Perform DTC confirmation procedure again.

GO TO 3.

PERFORM COMPONENT FUNCTION CHECK-1

Without CONSULT

1. Start engine and warm it up to the normal operating temperature.

2. Turn ignition switch OFF and wait at least 10 seconds.

3. Turn ignition switch ON.

4. Turn ignition switch OFF and wait at least 10 seconds.

5. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.

6. Let engine idle for 1 minute.

7. Check the voltage between ECM harness connector terminals under the following conditions.

   ECM			Condition	Voltage
   Connector	+	–
   	Terminal
   F78	41	35	Revving up to 4,000 rpm under no load at least 10 times	The voltage should be below 0.27 V at least once during this procedure.

Is the inspection result normal?

INSPECTION END

GO TO 6.

PERFORM COMPONENT FUNCTION CHECK-2

Check the voltage between ECM harness connector terminals under the following conditions.

Is the inspection result normal?

INSPECTION END

GO TO 7.

PERFORM COMPONENT FUNCTION CHECK-3

Check the voltage between ECM harness connector terminals under the following conditions.

Is the inspection result normal?

To check malfunction symptom before repair: Refer to Intermittent Incident.

Confirmation after repair: INSPECTION END

Proceed to Diagnosis Procedure.

INSPECTION START

Confirm the detected malfunction (A or B). Refer to DTC Description.

Which malfunction is detected?

GO TO 2.

GO TO 6.

CHECK HO2S2 CONNECTOR FOR WATER

1. Disconnect heated oxygen sensor 2 harness connector.

2. Check that water is not inside connectors.

Is the inspection result normal?

GO TO 3.

Repair or replace harness or connectors.

CHECK HO2S2 GROUND CIRCUIT

1. Disconnect heated oxygen sensor 2 harness connector.

2. Disconnect ECM harness connector.

3. Check the continuity between heated oxygen sensor 2 (HO2S2) harness connector and ECM harness connector.

   HO2S2			ECM		Continuity
   Bank	Connector	Terminal	Connector	Terminal
   1	F62	4	F78	35	Existed

4. Also check harness for short to ground and short to power.

Is the inspection result normal?

GO TO 4.

Repair open circuit, short to ground or short to power in harness or connectors.

CHECK HO2S2 INPUT SIGNAL CIRCUIT

1. Check the continuity between HO2S2 harness connector and ECM harness connector.

   HO2S2			ECM		Continuity
   Bank	Connector	Terminal	Connector	Terminal
   1	F62	3	F78	41	Existed

2. Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.

   HO2S2			Ground	Continuity
   Bank	Connector	Terminal
   1	F62	3	Ground	Not existed

   ECM		Ground	Continuity
   Connector	Terminal
   F78	41	Ground	Not existed

3. Also check harness for short to power.

Is the inspection result normal?

GO TO 5.

Repair open circuit, short to ground or short to power in harness or connectors.

CHECK HEATED OXYGEN SENSOR 2

Check heated oxygen sensor 2. Refer to Component Inspection.

Is the inspection result normal?

INSPECTION END

Replace malfunctioning heated oxygen sensor 2. Refer to Removal and Installation (bank 1).

CLEAR MIXTURE RATIO SELF-LEARNING VALUE

1. Clear the mixture ratio self-learning value. Refer to Description.

2. Run engine for at least 10 minutes at idle speed.

Is the 1st trip DTC P0172 detected? Is it difficult to start engine?

Perform trouble diagnosis for DTC P0172. Refer to DTC Description.

GO TO 7.

CHECK HO2S2 GROUND CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect heated oxygen sensor 2 harness connector.

3. Disconnect ECM harness connector.

4. Check the continuity between HO2S2 harness connector and ECM harness connector.

   HO2S2			ECM		Continuity
   Bank	Connector	Terminal	Connector	Terminal
   1	F62	4	F78	35	Existed

5. Also check harness for short to ground and short to power.

Is the inspection result normal?

GO TO 8.

Repair open circuit, short to ground or short to power in harness or connectors.

CHECK HO2S2 INPUT SIGNAL CIRCUIT

1. Check the continuity between HO2S2 harness connector and ECM harness connector.

   HO2S2			ECM		Continuity
   Bank	Connector	Terminal	Connector	Terminal
   1	F62	3	F78	41	Existed

2. Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.

   HO2S2			Ground	Continuity
   Bank	Connector	Terminal
   1	F62	3	Ground	Not existed

   ECM		Ground	Continuity
   Connector	Terminal
   F78	41	Ground	Not existed

3. Also check harness for short to power.

Is the inspection result normal?

GO TO 9.

Repair open circuit, short to ground or short to power in harness or connectors.

CHECK HEATED OXYGEN SENSOR 2

Check heated oxygen sensor 2. Refer to Component Inspection

Is the inspection result normal?

INSPECTION END

Replace malfunctioning heated oxygen sensor 2. Refer to Removal and Installation (bank 1).

INSPECTION START

Will CONSULT be used?

Will CONSULT be used?

GO TO 2.

GO TO 3.

CHECK HEATED OXYGEN SENSOR 2

With CONSULT

1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT.

2. Start engine and warm it up to the normal operating temperature.

3. Turn ignition switch OFF and wait at least 10 seconds.

4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.

5. Let engine idle for 1 minute.

6. Select “FUEL INJECTION” in “ACTIVE TEST” mode, and select “HO2S2 (B1)/(B2)” as the monitor item with CONSULT.

7. Check “HO2S2 (B1)/(B2)” at idle speed when adjusting “FUEL INJECTION” to ± 25%.

   

   	: The voltage should be above 0.72 V at least on time.
   	: The voltage should be below 0.27 V at least on time.

   “HO2S2 (B1)/(B2)” should be above 0.72 V at least once when the “FUEL INJECTION” is + 25%.

   “HO2S2 (B1)/(B2)” should be below 0.27 V at least once when the “FUEL INJECTION” is − 25%.

Is the inspection result normal?

INSPECTION END

Replace malfunctioning heated oxygen sensor 2. Refer to Removal and Installation (bank 1).

CHECK HEATED OXYGEN SENSOR 2-I

Without CONSULT

1. Start engine and warm it up to the normal operating temperature.

2. Turn ignition switch OFF and wait at least 10 seconds.

3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.

4. Let engine idle for 1 minute.

5. Check the voltage between ECM harness connector terminals under the following conditions.

   ECM			Condition	Voltage
   Connector	+	–
   	Terminal
   F78	41	35	Revving up to 4,000 rpm under no load at least 10 times	The voltage should be above 0.72 V at least once during this procedure. The voltage should be below 0.27 V at least once during this procedure.

Is the inspection result normal?

INSPECTION END

GO TO 4.

CHECK HEATED OXYGEN SENSOR 2-II

Check the voltage between ECM harness connector terminals under the following conditions.

Is the inspection result normal?

INSPECTION END

GO TO 5.

CHECK HEATED OXYGEN SENSOR 2-III

Check the voltage between ECM harness connector terminals under the following conditions.

Is the inspection result normal?

INSPECTION END

Replace malfunctioning heated oxygen sensor 2. Refer to Removal and Installation (bank 1).