Nissan Murano: Dtc/circuit Diagnosis / P0740 Torque Converter

DTC Description

DTC DETECTION LOGIC

POSSIBLE CAUSE

• Harness or connector (Torque converter clutch solenoid valve circuit is open or shorted to power supply)

• Torque converter clutch solenoid valve

FAIL-SAFE

• Start is slow

• Acceleration is slow

• Lock-up is not performed

CAUTION:

Be careful of the driving speed.

PREPARATION BEFORE WORK

If another "DTC CONFIRMATION PROCEDURE" occurs just before, turn ignition switch OFF and wait for at least 10 seconds, then perform the next test.

GO TO 2.

PREPARATION BEFORE OPERATION

With CONSULT

1. Start the engine.

2. Select “Data Monitor” in “TRANSMISSION”.

3. Select “FLUID TEMP”.

4. Confirm that the CVT fluid temperature is in the following range.

   FLUID TEMP

   : 20°C (68°F) or more

With GST

1. Start the engine.

2. Set the CVT fluid to 20°C (68°F) or more.

   NOTE:

   When the ambient temperature is 20°C (68°F), the CVT fluid usually increases to 50 to 80°C (122 to 176°F) with driving in an urban area for approximately 10 minutes.

Is the CVT fluid 20°C (68°F) or more?

GO TO 3.

1. Warm the transaxle.

2. GO TO 3.

CHECK DTC DETECTION

1. Drive the Nissan Murano vehicle.

2. Maintain the following conditions for 10 seconds or more.

   Selector lever	: “D” position
   Nissan Murano Vehicle speed	: 40 km/h (25 MPH) or more

3. Stop the vehicle.

4. Check the first trip DTC.

Is “P0740” detected?

Go to Diagnosis Procedure.

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

Confirmation after repair: INSPECTION END

CHECK CIRCUIT BETWEEN TCM AND CVT UNIT

1. Turn ignition switch OFF.

2. Disconnect TCM connector and CVT unit connector.

3. Check continuity between TCM harness connector terminal and CVT unit harness connector terminal.

   TCM		CVT unit		Continuity
   Connector	Terminal	Connector	Terminal
   F25	38	F44	5	Existed

Is the inspection result normal?

GO TO 2.

Repair or replace malfunctioning parts.

CHECK CIRCUIT BETWEEN CUT UNIT AND GROUND

Check resistance between CVT unit harness connector terminal and ground.

Is the inspection result normal?

Check intermittent incident. Refer to Intermittent Incident.

GO TO 3.

CHECK CIRCUIT BETWEEN CVT UNIT AND CONTROL VALVE

1. Disconnect control valve connector. Refer to Removal and Installation.

2. Check continuity between CVT unit harness connector terminal and control valve harness connector terminal.

Is the inspection result normal?

GO TO 4.

Replace terminal cord assembly. Refer to Removal and Installation.

CHECK CIRCUIT BETWEEN CONTROL VALVE AND GROUND

Check resistance between control valve harness connector terminal and ground.

Is the inspection result normal?

Check intermittent incident. Refer to Intermittent Incident.

There is malfunction of torque converter clutch solenoid valve. Replace control valve assembly. Refer to Removal and Installation.