Automatic Transmission System

A760E AUTOMATIC TRANSMISSION: ELECTRONIC CONTROLLED AUTOMATIC TRANSMISSION SYSTEM: P0500: Vehicle Speed Sensor "A"
P0500 - Vehicle Speed Sensor "A"

DESCRIPTION

The speed sensor SP2 detects the rotation speed of the transmission output shaft and sends signals to the ECM. The ECM determines the vehicle speed based on these signals. An AC voltage is generated in the speed sensor SP2 coil as the parking gear mounted on the rear planetary gear assembly rotates, and this voltage is sent to the ECM. The parking gear on the rear planetary gear is used as the timing rotor for this sensor.

The gear shift point and lock-up timing are controlled by the ECM based on the signals from this vehicle speed sensor and the throttle position sensor signal.









Reference (Using an oscilloscope):

Check the waveform between terminals SP2+ and SP2- of the ECM connector.





Standard:

Refer to the illustration.





MONITOR DESCRIPTION

The output speed sensor SP2 monitors the output shaft speed. The ECM controls the gearshift point and the lock up timing based on the signals from the output speed sensor SP2 and throttle position sensor.

If the ECM detects no signal from the output shaft speed sensor SP2 even while the vehicle is moving, it will conclude that is a malfunction of the output speed sensor SP2. The ECM will illuminate the MIL and set a DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Perform the universal trip to clear permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

1. DATA LIST

HINT
According to the Data List displayed by the Techstream, you can read the value of the switch, sensor, actuator and so on without parts removal. Reading the Data List as the first step of troubleshooting is one method to shorten labor 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.

(a) Warm up the engine.

(b) Turn the engine switch off.

(c) Connect the Techstream to the DLC3.

(d) Turn the engine switch on (IG).

(e) Turn on the tester.

(f) Select the item "Powertrain / ECT / Data List".

(g) According to the display on the tester, read the "Data List".





HINT
- SPD(SP2) is always 0 while driving:
Open or short in the sensor or circuit.
- SPD(SP2) value displayed on the tester is much lower than the actual vehicle speed:
Sensor trouble, improper installation, or intermittent connection trouble of the circuit.

PROCEDURE

1. INSPECT SPEED SENSOR INSTALLATION

(a) Check the speed sensor (SP2) installation.





OK:

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

NG -- SECURELY INSTALL SPEED SENSOR OR REPLACE SPEED SENSOR
OK -- Continue to next step.

2. INSPECT SPEED SENSOR (SP2)

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





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

Standard resistance:





NG -- REPLACE SPEED SENSOR (SP2)
OK -- Continue to next step.

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):





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ECM