Transmission. Lexus Gs430, Gs300. Uzs190 Grs190
A761E Automatic Transmission. Lexus Gs430, Gs300. Uzs190 Grs190
INSPECT SPEED SENSOR INSTALLATION
CHECK HARNESS AND CONNECTOR (SPEED SENSOR - ECM)
DTC 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.
| DTC No. | DTC Detection Condition | Trouble Area |
| P0500 | No speed sensor signal to ECM under following conditions: (1-trip detection logic) (a) Park/neutral position switch is OFF (b) Vehicle is being driven |
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Reference (Using an oscilloscope):
Check the waveform between terminals SP2+ and SP2- of the ECM connector.
- Standard:
- Refer to the illustration.
Terminal SP2+ - SP2- Tool setting 2 V/DIV, 20ms/DIV Vehicle condition Vehicle speed 20 km/h (12 mph)
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.
WIRING DIAGRAM
INSPECTION PROCEDURE
| DATA LIST |
- HINT:
- Using the intelligent tester 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 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.
Warm up the engine.
Turn the engine switch off.
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) position.
Turn on the tester.
Select the item "Enter / Power train / ECT / Data List".
Follow the instructions on the tester and read the Data List.
| Item | Measurement Item/ Range (display | Normal Condition |
| SPD (SP2) | Output shaft Speed/ min.: 0 km/h (0 mph) max.: 255 km/h (158 mph) | Vehicle stopped: 0 km/h (0 mph)
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- HINT:
- SPD (SP2) is always 0 while driving:
Open or short in the sensor or circuit. - The 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.
| 1.INSPECT SPEED SENSOR INSTALLATION |
Check the speed sensor (SP2) installation.
- OK:
- The installation bolt is tightened properly and there is no clearance between the sensor and transmission case.
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| OK | |
| 2.INSPECT SPEED SENSOR (SP2) |
Disconnect the speed sensor connector from the transmission.
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Measure the resistance according to the value(s) in the table below.
- Resistance:
Tester Connection Specified Condition
20°C (68°F)1 - 2 560 to 680 Ω
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| OK | |
| 3.CHECK HARNESS AND CONNECTOR (SPEED SENSOR - ECM) |
Connect the speed sensor connector.
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Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
- Resistance:
Tester Connection Specified Condition
20°C (68°F)E7 - 23 (SP2+) - E7 - 22 (SP2-) 560 to 680 Ω
Measure the resistance according to the value(s) in the table below.
- Resistance (Check for short):
Tester Connection Specified Condition E7 - 23 (SP2+) - Body ground 10 kΩ or higher E7 - 22 (SP2-) - Body ground ↑
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| OK | ||
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