U151F Automatic Transaxle

U151F AUTOMATIC TRANSAXLE: AUTOMATIC TRANSAXLE SYSTEM: P0793: Intermediate Shaft Speed Sensor "A"
P0793 - Intermediate Shaft Speed Sensor "A"

DESCRIPTION

This sensor detects the rotation speed of the counter gear. By comparing the counter gear speed signal (NC) with the direct clutch speed sensor signal (NT), the ECM detects the shift timing of the gears and approximately controls the engine torque and hydraulic pressure according to various conditions. Thus smooth gear shifting is performed.





MONITOR DESCRIPTION

The NC terminal of the ECM detects revolution signals from speed sensor NC (counter gear rpm). The ECM calculates gear shifts by comparing speed sensor NT with speed sensor NC.

While the vehicle is operating in the 2nd, 3rd, 4th or 5th gear position with the shift lever on D, if the counter gear revolution is less than 300 rpm*1 and 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 25 km/h (16 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 .

HINT
Using Techstream's Data List allows switch, sensor, actuator and other item values to be read without removing any parts. Reading the Data List early in troubleshooting is one way to save 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 Techstream to the DLC3.

4. Turn the ignition switch to ON and turn the Techstream on.

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

6. Follow the instructions on the Techstream and read the Data List.

ECM:





HINT
- SPD (NC) is always 0 rpm while driving:
- Open or short in the sensor or circuit.
- SPD (NC) is always more than 0 and less than 300 rpm while driving the vehicle at 50 km/h (31 mph) or more:
- Sensor trouble, improper installation, or intermittent connection trouble of the circuit.

PROCEDURE

1. INSPECT SPEED SENSOR (INSTALLATION)





(a) Check the speed sensor NC installation.

OK:

Installation bolt is tightened properly and there is no clearance between the sensor and transaxle case.

NG -- REPLACE SPEED SENSOR NC
OK -- Continue to next step.

2. INSPECT SPEED SENSOR NC





(a) Disconnect the B24 sensor connector from the transaxle.

(b) Measure the resistance of the sensor.

Standard resistance:





NG -- REPLACE SPEED SENSOR NC
OK -- Continue to next step.

3. CHECK WIRE HARNESS (SPEED SENSOR - ECM)





(a) Disconnect the B30 ECM connector.

(b) Measure the resistance of the wire harness side connector.

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR

OK -- REPLACE ECM