Nissan Murano: Dtc/circuit Diagnosis / P0181 Ftt Sensor

DTC Description

DTC DETECTION LOGIC

1. Rationally incorrect voltage from the sensor is sent to ECM, compared with the voltage signals from ECT sensor and intake air temperature sensor.

2. The comparison result of signals transmitted to ECM from each temperature sensor (IAT sensor, ECT sensor, EOT sensor, and FTT sensor) shows that the voltage signal of the FTT sensor is higher/lower than that of other temperature sensors when the engine is started with its cold state.

POSSIBLE CAUSE

P0181 - 1

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

• FTT sensor

P0181 - 2

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

• FTT sensor

FAIL-SAFE

Not applicable

INSPECTION START

Is it necessary to erase permanent DTC?

GO TO 7.

GO TO 2.

PRECONDITIONING

If DTC CONFIRMATION PROCEDURE has been previously conducted, always perform the following procedure 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 3.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION 1-I

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

2. Check 1st trip DTC.

Is 1st trip DTC detected?

Proceed to Diagnosis Procedure.

GO TO 4.

CHECK ENGINE COOLANT TEMPERATURE

With CONSULT

1. Select “COOLANT TEMP/S” in “DATA MONITOR” with CONSULT.

2. Check “COOLANT TEMP/S” value.

With GST

Follow the procedure “With CONSULT” above.

“COOLANT TEMP/S” less than 60°C (140°F)?

INSPECTION END

GO TO 5.

PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION 1-II

With CONSULT

1. Cool engine down until “COOLANT TEMP/S” is less than 60°C (140°F).

2. Wait at least 10 seconds.

3. Check 1st trip DTC.

With GST

Follow the procedure “With CONSULT” above.

Is 1st trip DTC detected?

Proceed to Diagnosis Procedure.

GO TO 6.

CHECK FUEL TANK TEMPERATURE (FTT) SENSOR

1. Turn ignition switch OFF.

2. Disconnect fuel level sensor unit and fuel pump harness connector.

3. Remove fuel level sensor unit. Refer to Removal and Installation.

4. Check resistance between fuel level sensor unit and fuel pump terminals by heating with hot water as shown in the figure.

   

   Terminals	Condition		Resistance (kΩ)
   1 and 3	Temperature [°C (°F)]	20 (68)	2.3 – 2.7
   		50 (122)	0.79 – 0.90

Is the inspection result normal?

INSPECTION END

Proceed to Diagnosis Procedure.

PRECONDITIONING

If DTC CONFIRMATION PROCEDURE has been previously conducted, always perform the following procedure 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.

TESTING CONDITION:

• Before performing the following procedure, do not add fuel.

• Before performing the following procedure, check that fuel level is between 1/4 and 4/4.

• Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.

GO TO 8.

PERFORM DTC CONFIRMATION PROCEDURE 2

1. Move the Nissan Murano vehicle to a cool place.

   NOTE:

   Cool the vehicle in an environment of ambient air temperature between −10°C (14°F) and 35°C (95°F).

2. Turn ignition switch OFF and leave the Nissan Murano vehicle for 12 hours.

   CAUTION:

   Never turn ignition switch ON during this procedure.

   NOTE:

   The Nissan Murano vehicle must be cooled with the hood open.

3. Start engine and let it idle for 5 minutes or more.

   CAUTION:

   Never turn ignition switch OFF during idling.

4. Check 1st trip DTC.

Is 1st trip DTC detected?

Proceed to Diagnosis Procedure.

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

Confirmation after repair: INSPECTION END

INSPECTION START

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

Which malfunction is detected?

GO TO 2.

GO TO 5.

CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY

1. Turn ignition switch OFF.

2. Disconnect fuel level sensor unit and fuel pump harness connector.

3. Turn ignition switch ON.

4. Check the voltage between fuel level sensor unit and fuel pump harness connector and ground.

   Fuel level sensor unit and fuel pump		Ground	Voltage
   Connector	Terminal
   B72	3	Ground	Approx. 5 V

Is the inspection result normal?

GO TO 4.

GO TO 3.

CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check the continuity between fuel tank temperature sensor harness connector and ECM harness connector.

Is the inspection result normal?

Perform the trouble diagnosis for power supply circuit.

Repair or replace error-detected parts.

CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check the continuity between fuel level sensor unit and fuel pump harness connector and ECM harness connector.

   Fuel level sensor unit and fuel pump		ECM		Continuity
   Connector	Terminal	Connector	Terminal
   B72	1	E32	148	Existed

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

Is the inspection result normal?

GO TO 5.

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

CHECK FUEL TANK TEMPERATURE SENSOR

Check fuel tank temperature sensor. Refer to Component Inspection.

Is the inspection result normal?

INSPECTION END

Replace fuel level sensor unit and fuel pump. Refer to Removal and Installation.

CHECK FUEL TANK TEMPERATURE SENSOR

1. Turn ignition switch OFF.

2. Remove fuel level sensor unit. Refer to Removal and Installation.

3. Check resistance between “fuel level sensor unit and fuel pump” terminals by heating with hot water as shown in the figure.

   

   Mass air flow sensor		Condition		Resistance (kΩ)
   +	−
   Terminals
   3	1	Temperature [°C (°F)]	20 (68)	2.3 - 2.7 kΩ
   			50 (122)	0.79 - 0.90 kΩ

Is the inspection result normal?

INSPECTION END

Replace fuel level sensor unit and fuel pump. Refer to Removal and Installation.