COUPLING 4N9639 - Caterpillar

A passive two-wire magnetic frequency-type sensor converts mechanical motion to an AC voltage. The torque converter output speed sensor measures torque converter output speed in the range of 25 to 3000 rpm. The speed sensor information is also used by the Power Train ECM to set and adjust transmission shift points. Transmission speed sensors may be used in pairs.Pressure Sensors
Implement Pump Pressure Sensor
Implement Pump Load Sense Pressure Sensor
Lift Cylinder Head End Pressure Sensor (If Equipped)
Lift Cylinder Rod End Pressure Sensor (If Equipped)
Steering Pump Oil Pressure Sensors
Illustration 9 g02571841
The pressure sensor sends a PWM signal to the implement ECM indicating system pressure. The duty cycle of the signal will vary in proportion to the system pressure. These PWM signals are inputs to the Implement ECM.Position Sensors
Steering Position Sensor (STIC Control)
Illustration 10 g01444766
The sensor is designed to tell the ECM the position of the lever. The operator controls the range through left and right movements, and the sensor sends the signal to the ECM. The sensor generates a PWM signal continuously. The duty cycle of the signal varies in proportion to the position of the lever. Refer to Illustration 4 for a description of the terminals and connections to the ECMs.Steering Spool Postion sensor
Illustration 11 g03566490
The sensor is designed to tell the ECM the position of the steering control spool. The sensor generates an analog voltage signal.Lock Out Switch
Keyswitch
Illustration 12 g03003739
Key Start SwitchThe key start switch is an input of the transmission electronic control module (ECM). The key start switch informs the transmission ECM of an attempt to start the engine. The transmission ECM then initiates the neutral start function. During normal machine operation, the start terminal of the key start switch is open. When the key start switch is turned to the START position, the start terminal closes to the +battery. The +battery voltage is present at connector contact J2-1 of the transmission ECM. When all starting conditions are satisfied, the transmission ECM sends a +battery signal to the connector contact J2-7. The connector contact J2-7 is for the start relay that engages the starter for engine cranking.Note: When the key start switch is in the ON position, a +battery signal is sent to connector contact J1-1. With +battery signal to connector contact J1-1 will activate the transmission ECM.Note: After the key start switch is initially turned to the START position, the switch will not return to the START position from the ON position. The switch must be turned to the OFF position first. Then, the switch can be turned to the START position.Outputs
The ECMs respond to decisions by sending electrical signals to the outputs. The outputs can create an action or the outputs can provide information to the operator or the service technician. The outputs of the ECM are listed in Tables 3 and 3.Solenoids
Steering Solenoids
Illustration 13 g03566528
The steering solenoids are located on the steering control valve. The solenoid functions as a proportional valve. The solenoid modulates hydraulic pressure to move the steering control spool. The ECM increases the PWM Driver to the