A340F Automatic Transmission System

A340F AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM: P0717: Turbine Speed Sensor Circuit No Signal
P0717 - Turbine Speed Sensor Circuit No Signal

DESCRIPTION

The sensor detects the rotation speed of the turbine which shows the input revolution of the transmission.

By comparing the input turbine speed signal (NCO) with the counter gear speed sensor signal (SP2), the ECM detects the shift timing of the gears and appropriately controls the engine torque and hydraulic pressure according to various conditions. As a result, the gears shift smoothly.





Using an oscilloscope:

Check the waveform between terminals NCO+ and NCO- of the ECM connector.





Standard:

Refer to the illustration.





MONITOR DESCRIPTION

This DTC indicates that a pulse is not output from the speed sensor NCO (Turbine (input) speed sensor) or is weak. The NCO terminal of the ECM detects the pulse signal from speed sensor (NCO) (input speed). The ECM outputs a gear shift signal comparing the speed sensor (NCO) with the output speed sensor (SP2).

If the input shaft revolution is less than 300 rpm*1 although the output shaft revolution is 500 rpm or more*2, the ECM detects the trouble, illuminates the MIL and stores the DTC.

*1: A pulse is not output or is irregularly output.

*2: The vehicle speed is approximately 50 km/h (31 mph) or more.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





COMPONENT OPERATING RANGE





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Perform the universal trip to clear permanent DTCs DTC Check / Clear.

HINT
Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

NOTICE:
In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.

1. Warm up the engine.

2. Turn the ignition switch off.

3. Connect the Techstream to the DLC3.

4. Turn the ignition switch to ON.

5. Turn the Techstream on.

6. Enter the following menus: Powertrain / Engine and ECT / Data List.

7. According to the display on the Techstream, read the Data List.

Engine and ECT





HINT
* SPD (NC0) is always 0 while driving:
Open or short in the sensor or circuit.
* SPD (NC0) is always more than 0 and less than 300 rpm while driving the vehicle at 50 km/h (30 mph) or more:
Sensor trouble, improper installation, or intermittent connection trouble in the circuit.

PROCEDURE

1. INSPECT SPEED SENSOR (NCO) INSTALLATION

(a) Check the speed sensor (NCO) installation.





OK:

The installation bolt is tightened properly and there is no clearance between the sensor and transmission case.

Text in Illustration





NG -- SECURELY INSTALL OR REPLACE SPEED SENSOR (NCO) Installation
OK -- Continue to next step.

2. INSPECT SPEED SENSOR (NCO)

(a) Disconnect the speed sensor (NCO) connector.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPLACE SPEED SENSOR (NCO) Removal
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (SPEED SENSOR (NCO) - ECM)

(a) Disconnect the ECM connector.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ECM Removal