DISC-THROTTLE 6L5287 - Caterpillar

938 Differential Lock Solenoid
Illustration 17 g03796216
The differential lock solenoid is located in the front right inner frame.
The differential lock solenoid is activated by the ECM when the operator selects the differential lock. The differential lock solenoid controls hydraulic oil flow to the differential lock for locking and unlocking the differential. The differential lock solenoid is a two position hydraulic solenoid valve.Hydrostatic Interlock Solenoid
Illustration 18 g03796221
The hydrostatic interlock solenoid is located in the valve block attached to the hydrostatic drive pump.
The hydrostatic interlock solenoid controls the flow of pilot oil to the hydrostatic pump control valve. The hydrostatic interlock solenoid is a two position hydraulic solenoid valve. Hydrostatic Pump Forward/Reverse Solenoids
Illustration 19 g03796223
Left side view of hydrostatic drive pump
For the control of the hydrostatic pump solenoids, the ECM applies a current amount that corresponds to signals from operator and machine inputs. The hydrostatic pump forward and reverse solenoids control pilot oil flow to the actuating piston. The actuating piston controls the pilot valve. The pilot valve controls pilot oil to the displacement piston. The displacement piston actuates the pump swash plate which increases pump displacement. The hydrostatic pump forward and reverse solenoids have a variable position based on the amount of PWM signal supplied by the ECM. Increasing or decreasing PWM signal is based on operator and machine inputs.Hydrostatic Motor One And Two Displacement Solenoids
Illustration 20 g03796226
Left front view of transmission and motors.
(A) Hydrostatic Motor 1 Displacement Solenoid
(B) Hydrostatic Motor 2 Displacement Solenoid The ECM provides a current amount that corresponds to the input signals from the operator and machine inputs. The current provided by the ECM controls the displacement of the hydrostatic motors. The hydrostatic motor solenoids are a variable position valve based on the amount of PWM signal supplied by the ECM. Increasing or decreasing PWM signal is based on operator and machine inputs.Hydrostatic Transmission Motor Clutch Solenoid
Illustration 21 g03796227
Left front view of transmission
The hydrostatic motor clutch solenoid is controlled by the ECM. Based on operator and machine inputs the ECM controls the PWM signal to the solenoid. The hydrostatic motor clutch solenoid has a variable valve position based on the PWM signal applied by the ECM.Relays
Illustration 22 g02748058
Typical example of a relay
Backup Alarm/Auto Reverse Light Relay
Illustration 23 g02748420
The Backup Alarm/Auto Reverse Light Relay is located behind the panel shown on the left side of the cab exterior.
Relay coil resistance is measured at pins 85 and 86. Relay coil resistance is 228 ohms 22.8 ohms at 25° C (77° F).Data Link
Cat Data Link
The Cat Data Link is an input/output of the ECM. The data link uses the connector for the service port in order to communicate with the Caterpillar Electronic Technician. A data link connection is provided