Toyota Sienna Service Manual: Turbine Speed Sensor Circuit No Signal

DESCRIPTION

This sensor detects the rotation speed of the input turbine. By comparing the input turbine speed signal (NT) with the counter gear speed sensor signal (NC), the ECM detects the shift timing of the gears and appropriately controls the engine torque and hydraulic pressure according to various conditions. Thus, providing smooth gear shift.

Reference (Using an oscilloscope): Check the waveform between terminals NT+ and NT- of the ECM connector.

Standard: Refer to the illustration.

MONITOR DESCRIPTION

The NT terminal of the ECM detects a revolution signal from the speed sensor (NT) (input RPM). The ECM calculates a gearshift comparing the speed sensor (NT) with the speed sensor (NC).

While the vehicle is operating in 2nd, 3rd, 4th or 5th gear in the shift position of D, if the input shaft revolution is less than 300 rpm *1although the output shaft revolution is more than 1,000 rpm *2, the ECM detects the trouble, illuminates the MIL and stores the DTC.

*1: Pulse is not output or is irregularly output.

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

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

WIRING DIAGRAM

INSPECTION PROCEDURE

1 INSPECT SPEED SENSOR INSTALLATION

(a) Check the speed sensor installation.

OK: The installation bolt is tightened properly and there is no clearance between the sensor and transaxle case.

2 INSPECT SPEED SENSOR (NT)

(a) Disconnect the speed sensor connector from the transaxle.

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

Standard resistance

3 CHECK HARNESS AND CONNECTOR (SPEED SENSOR - ECM)

(a) Connect the speed sensor connector.

(b) Disconnect the ECM connector.

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

Standard resistance

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

Standard resistance (Check for short)

REPLACE ECM