KIT-DISC 1844390 - Caterpillar

Illustration 4 g01213770
Engine Speed Sensor
The engine speed sensor for the transmission is a magnetic sensor.The engine speed sensor is an input to the ECU. The sensor is designed to inform the ECU about the speed of the engine. The ECU uses the information from the speed sensor in order to calibrate the transmission solenoids. The ECU uses the information from the speed sensor in order to enable the lockup clutch. Also, the information is used in order to disable the lockup clutch. The lockup clutch is turned off if the engine speed is too low. The lockup clutch is turned on if the engine speed is too high. This is done in order to prevent overspeeds of the engine or stalling of the engine.The engine speed sensor is a frequency sensor. The speed sensor is located on the flywheel housing. The sensor generates an AC signal from the ring gear teeth as the teeth pass the sensor. The ECU measures the frequency of the signal and the ECU responds accordingly to the signal. The engine speed and the diagnostic status of the sensor are available to all modules through the J1939 data link.The engine speed sensor has a connector with two contacts. The sensor connects to the ECU through contacts J1-2 and contact J1-3.Transmission Output Speed Sensor (1) and Transmission Output Speed Sensor (2)
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Transmission Output Speed Sensor (1)
Transmission Output Speed Sensor (2)
The transmission output speed sensors are an input to the ECU. The transmission output speed sensor informs the ECU about the speed of the transmission output shaft. The ECU uses the information from the transmission output speed sensors in order to shift the transmission properly. The transmission output speed sensor is a magnetic sensor. The output speed sensor is a “bolt and go” sensor that is a high output speed sensor. There are two output speed sensors for each transmission. The sensors read the same speed. The second sensor provides a backup value in the event of a single sensor failure. The direction is also provided when both sensors are used. The first sensor is spaced one quarter of a tooth off from the second sensor. The space is necessary in order to provide a direction to the ECU. When one of the sensors goes bad or a failure arises a diagnostic code is issued, but a valid engine speed is still present. The transmission output speed sensor (1) connects to the ECU through contacts J1-6 and contact J1-7. The transmission output speed sensor (2) connects to the ECU through contacts J1-8 and contact J1-9.Transmission Input Speed Sensor (Torque Converter Output Speed)
Illustration 6 g01213770The speed sensor is an input to the ECU. The sensor informs the Transmission ECU about the speed of the transmission input shaft. The ECU uses the information from the sensor in order to validate the signals for the output speed sensors. When the output speed sensor fails, an amber warning lamp is activated. The ECU also uses the information to aid in calibration of