EJECTOR-ROCK 7D0554 - Caterpillar

Inputs for the Chassis ECM that are Used by the Transmission ECM
The following inputs to the Chassis ECM are also used by the Transmission ECM:Shift Lever
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(1) Shift lever The shift lever (1) is mechanically positioned. The shift lever (1) provides the Chassis Electronic Control Module (Chassis ECM) with information about the position of the shift lever (1). The Chassis ECM then sends this information to the Transmission Electronic Control Module (Transmission ECM). The Transmission ECM uses this information in order to determine the correct speed for the transmission.Manual Shifting
In the manual shifting mode, the Transmission Electronic Control Module keeps the transmission in the same gear that has been selected. Manual operation includes REVERSE, NEUTRAL, and FIRST gears. The maximum forward gear is also the minimum automatic gear.Automatic Shifting
The Transmission ECM provides fully automatic shifting from the minimum automatic gear to the top gear limit.In the automatic shifting mode, the operator sets shift lever (1) to the maximum gear range that is desired. All of the automatic upshifts and the automatic downshifts are dependent on the speed of the machine. The automatic upshifts and automatic downshifts are preprogrammed in the Transmission ECM for each gear. The shift points are raised slightly by the use of the retarder or by the service brakes. During normal shifting, the Transmission ECM does not allow a turnaround shift until approximately 4.5 seconds after a shift occurs. This delay allows mechanical conditions to stabilize before an opposite shift occurs. This delay also allows hydraulic conditions to stabilize before an opposite shift occurs. Inputs from the service/retarder brake and from the parking and secondary brake eliminate this feature.Hoist Control
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(1) LOWER position
(2) FLOAT position
(3) HOLD position
(4) RAISE position The hoist control is located to the right of the operator's seat. The hoist control has four positions: RAISE, HOLD, FLOAT and LOWER. The machine should normally be operated with the hoist control in the FLOAT position.The hoist control is connected to the hoist control position sensor. The hoist control position sensor sends electrical signals to the Chassis Electronic Control Module. See the hydraulic system System Operation, "Position Sensor (Hoist Control)" for additional information.When the hoist control is released a spring will move the hoist control from the RAISE position to the HOLD position or from the LOWER position to the FLOAT position.Hoist Position Sensor
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Location of the hoist control position sensor
The position sensor for the hoist control is located in the center operator's console. The hoist control position sensor is a Pulse Width Modulation position sensor. The hoist control postion sensor sends duty cycle signals to the Power Train Electronic Control Module (Power Train ECM).The Power Train ECM uses these signals to energize the appropriate hoist proportioning solenoid on the hoist control valve. These hoist propertioning solenoids will move the spool in the hoist control valve. This will cause oil to be sent to the hoist cylinders in order to move the dump body.The signal from the hoist control position sensor is also used to