BOX GP-BATTERY 8W4405 - Caterpillar

Power Train Electronic Control System
Illustration 1 g00787708
Block diagram of the power train electronic control system (1) Service tool connector (2) CAT Data Link (3) Caterpillar Monitoring System (4) Caterpillar Monitoring System service connector (5) Electronic control module (ECM) (6) Modulating Valve (torque converter lockup clutch) (7) Modulating valves (electronic clutch pressure control )(six) (8) Transmission control (9) Engine (10) Transmission latching solenoid (AWR1-454) (11) Engine speed sensor (12) Sensor for the oil filter bypass (13) Torque converter (14) Torque converter output speed sensor (15) Transmission (16) Transmission output speed sensors (two) (17) Transmission oil temperature sensor (18) Pressure sensor for the latching rail (AWR1-454)Six hydraulically activated clutches in transmission (7) provide eight forward speeds and one reverse speed. Speed selections and direction selections are made manually by using transmission control (8). The power train electronic control system electronically controls transmission shifts. In order for the transmission to be shifted to the desired speed and the desired direction, the ECM (5) receives the operator input from transmission control (8). The ECM sends a signal to the modulating valves for the clutches that are selected. The output signal energizes the solenoids of the clutches that are selected. The output signal de-energizes the solenoids of the clutches that need to be released. The modulating valves electronically modulate the oil pressure of the clutches that are selected. A modulating valve is also used to control oil pressure to the torque converter lockup clutch. The torque converter lockup clutch provides direct drive between the engine and the transmission planetary.The power train ECM uses input signals from the following components to ensure steady engagement of the clutches: engine speed sensor (11), torque converter output speed sensor (14), transmission output speed sensors (16) and transmission oil temperature sensor (17) .The power train ECM also controls the following functions: interaxle differential lock, axle differential locks, hoist control and secondary steering system.Electronic Control Module
The electronic control module (ECM) is located at the right rear side of the cab. The ECM shifts the transmission. The transmission control sends the operator input to the ECM. The operator input indicates the desired speed for the transmission and the desired direction for the transmission. The ECM makes decisions that are based on the input information and on the memory information. After the ECM receives the input information and the memory information, the ECM sends a corresponding response to the outputs. The inputs and the outputs are connected to the machine harness by two 40-pin connectors.Inputs
The machine has several input devices. Input devices inform the ECM of the operating conditions of the machine. The machine has two types of inputs, switch inputs and sensor inputs. The switch inputs of the ECM are provided with the following signals from the switches: an open, a ground and a +battery. Sensors provide a constantly changing signal to the ECM. Outputs
The ECM responds to decisions by sending electrical signals through the outputs. The outputs can create an action or the outputs can provide information to the ECM.