COUPLING AS- 5313462 - Caterpillar

Power Distribution
Illustration 1 g06027142
Electrical Schematic
(1) From engine start switch relay
(2) From Wake-up fuse
(3) From machine ECM fuse
(4) Machine ECM
(5) Engine ECM
(6) CAN resistor
(7) Fan solenoid
(8) Inlet air temperature sensor
(9) Hydraulic oil temperature sensor
(10) Engine coolant temperature sensor
(11) CAN resistorWhen the engine start switch is in the ON position power transfers to the following fuses and relays:
Engine start switch relay
Wake-up fuse
Machine ECM fusePower transfers from engine start switch relay (1) to terminal "J1-69" of engine ECM (5). The voltage signal from the engine start switch relay provides the wake-up signal for the ECM.Power transfers from wake-up fuse (2) to terminal "J1-84", "J1-85"" and ",J1-86" of engine ECM (5). The voltage from the wake-up fuse provides the main power source for the ECM. The engine ECM is grounded at terminal "J1-81", "J1-82"and "J1-83".Power transfers from machine ECM fuse (3) to terminal "C3-36" and terminal "C3-38" of machine ECM (4). Voltage from the machine ECM fuse provides a wake-up signal and main power supply to the ECM. The machine ECM is grounded at terminal "C3-35" and terminal "C3-37".CAN Communication
After machine ECM (7) receives power, the ECM begins to monitor the CAN bus. Engine ECM (5) the machine ECM communicate through CAN communication lines. CAN resistors (6) and (11) act as termination resistors.Sensor Input
When engine ECM (5) is active, the ECM monitors the The following sensors:
Inlet air temperature sensor (8)
Hydraulic oil temperature sensor (9)
Engine coolant temperature sensor (10)Inlet air temperature sensor (8) is a resistance sensor. Engine ECM (5) passively monitors input from the sensor at terminal "J1-34". The inlet air temperature sensor is grounded at terminal "J1-29" of the ECM. Software in the engine ECM converts the signal at terminal "J1-34" into a temperature value. The temperature information is sent to machine ECM (4) through CAN communications lines.Hydraulic oil temperature sensor (9) is a resistance sensor. Engine ECM (5) passively monitors input from the sensor at terminal "J1-33". The sensor is grounded at the machine frame. Software in the engine ECM converts the signal at terminal "J1-16" into a temperature value. The temperature information is sent to machine ECM (4) through CAN communications lines.Engine coolant temperature sensor (10) is a resistance sensor. Engine ECM (5) passively monitors input from the sensor at terminal "J2-43". The engine coolant temperature sensor is grounded at terminal "J2-37" of the ECM. Software in the engine ECM converts the signal at terminal "J2-43" into a temperature value. The temperature information is sent to machine ECM (4) through CAN communications lines.Fan Control Logic
Machine ECM (4) regulates fan speed based on temperature sensor input. The ECM evaluates input signals from the above sensors to determine the appropriate output signal to be sent to fan solenoid (7). The machine ECM sends the output signal from terminal "C2-49" to contact "1" of the fan solenoid. Contact "2" of the solenoid is grounded at the machine frame.To calculate the target fan speed, software in machine ECM (4) compares temperature sensor values to programmed set points. When the temperature values are less than