RING 1L9350 - Caterpillar

Speed Mode And Direction Function
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Speed mode and direction function.Speed Mode and direction are determined by the position of the speed/direction control lever. The lever moves in an upside-down "Y" pattern. Movement of the lever to the right is FORWARD and movement of the lever to the left is REVERSE. Zero speed (NEUTRAL) is achieved when the lever is in the center part of the "Y" pattern. The parking brake is applied when the lever is in the tip of the upside-down "Y" pattern. The ECM sends current to the solenoids that correspond to the speed and the direction that is selected by the operator. When the speed mode switch is placed in the Work Mode position, speed is reduced to 70 percent of the normal speed. Normal speed is the speed that results when the speed mode switch is placed in the Travel Mode position.Steering Function
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Steering functionThe ECM monitors the position of the left and right steering pedals. The synchronizing valve is open when the steering pedals are not pressed. This valve connects both of the FORWARD drive pressures and both of the REVERSE drive pressures together. The LEFT drive pressure and the RIGHT drive pressure are equal. The equal pressure ensures that the machine will track straight. As a pedal is pressed, the ECM reduces the speed of the appropriate track which causes the machine to turn in the selected direction. When a steering pedal is pressed, the synchronizing valve is closed in order to allow left and right tracks to operate independently. When a pedal is pressed all the way, the track will slow down and the track will reverse direction. The machine will counterrotate.Braking And Anti-Rollback Function
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Braking and anti-rollback functionThe ECM monitors the position of the center brake pedal. When the pedal is pressed, the ECM reduces the speed of the machine in proportion to the position of the pedal. At the bottom of pedal travel, the mechanical brake is actuated. An anti-rollback function gives the operator the ability to preload the transmission against the brake. The anti-rollback function keeps the machine from rolling downhill while the machine is performing stopping operations and restarting operations on a slope. Engine Underspeed Function
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Engine underspeed functionThe ECM determines engine speed by reading the signal from the engine speed sensor. The engine speed will decrease as power demands are increased. The decrease will occur if power is demanded by the implements or if power is demanded by the transmission. If the engine speed decreases below a specific value, the ECM will reduce the machine speed. The ECM makes the reduction in order to reduce the power demand on the engine. This reduction keeps the engine from stalling.Air Inlet Heater Control
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Air inlet heater controlThe ECM for the hydrostatic transmission monitors engine speed, engine coolant temperature, and the status of the air inlet heater