The Machine ECM will make decisions that are based on input data information and programming parameters that have been flashed to the ECM memory. After the ECM receives the input information, the ECM determines the correct response and sends an output signal to the appropriate device. The internal input circuits and the internal output circuits of the ECM are connected to the machine wiring harness by two contact connectors (J1 and J2).
Note: The ECM is not serviceable. If the ECM is damaged, the ECM must be replaced. The ECM failure is unlikely. If the ECM failure is suspected, contact the Technical Communicator at a local dealership for possible consultation with AVSpare before replacing the ECM. Replace the ECM only after all the other possible causes of a particular problem have been investigated.
To aid in diagnostics of certain types of electrical circuits that are controlled by the ECM, an internal "pull up voltage" is connected to ECM switch and sensor signal input contacts. An above normal voltage is internally connected to the ECM signal input circuit through a resistor.
During normal operation, the switch or sensor signal will hold the circuit low or at a certain signal amplitude, however, circuit conditions such as a loss of power to the component, a disconnection, or an open circuit will allow the circuit to be pulled high by the ECM pull-up voltage. The pull-up voltage will result in an above normal voltage condition at the ECM contact. As a result, the ECM will activate an FMI 03 (voltage above normal) diagnostic code for the affected circuit.
The types of ECM input circuits that have pull-up voltage present are:
- Pulse Width Modulated (PWM) sensor input circuits
- Switch to ground switch input circuits
- Active analog (voltage) input signal circuits
- Passive analog (resistance) input signal circuits
To aid in diagnostics of electrical circuits that are controlled by the ECM, an internal "pull down voltage" is connected to ECM switch to battery type input circuits.
During normal operation, the switch contacts that are allowing the connection to a voltage source will hold the circuit high. When circuit conditions such as a loss of power to the switch supply voltage, a disconnection in the switch circuit or an open circuit will allow the circuit to be pulled low by the ECM pull-down voltage. The pull-down voltage will result in a below normal voltage condition at the ECM contact. As a result, the ECM will activate an FMI 04 (voltage below normal) diagnostic code for the affected circuit.
The machine has several different types of input devices. The ECM receives machine status information from the input devices and determines the correct output action that is needed to control machine operations based on memory and software parameters. The machine utilizes the following types of inputs: switch type and sensor type.
Switches provide signals to the switch inputs of the ECM. The possible outputs of a switch are listed: an open signal, a grounded signal and + battery signal.
Sensors provide an electrical signal to the ECM that constantly changes. The sensor input to the ECM can be one of several different types of electrical signals such as: pulse width modulated (PWM) signals, voltage signals, and frequency input signals. Each possible input to the Machine ECM is listed in the tables for the connectors.
The ECM sends electrical signals through the outputs. The outputs can create an action or the outputs can provide information to the ECM. The ECM can send output signals to the system components in one of several different electrical signal types such as: driver outputs, sinking driver outputs, sensor power supply outputs, and data link outputs. The possible outputs for the Machine ECM are listed in the tables for the connectors.
Communication between the Machine ECM and the other control modules on the machine is conducted over data link circuits. The data link circuits allow the sharing of information with other electronic control modules. The data link circuits are bidirectional. The data link circuit allows the ECM to send information and to receive information.
The ECM supports two types of data link systems.
- Cat® Data Link
- SAE J1939 Data Link
The two types of data links are the main structure for communication between all the control modules on the machine. More than one CAN data link system can be present on a machine. Dedicated CAN data link circuits can be used for communication between specific controls on the machine.
Communication between the Machine ECM and the other control modules on the machine are conducted over the J1939 Data Link circuit that is connected to each control module. The ECMs use the Cat Data Link to send and receive information from the Cat® Electronic Technician (Cat ET) Service Tool.
A module identifier (MID) is assigned to each ECM on a machine. The MID for Machine ECM 1 is 299. The MID for Machine ECM 2 is 432.
Note: The following tables list every possible connection for the Machine ECM. Depending on the attachments that are installed on your machine, some of the listed circuits may not be present.
Machine ECM #1 Connector J1 Contact Descriptions (1) | ||
---|---|---|
No. | Function | Type |
1 | Ground | Ground |
2 | PRV 8-10 Return | PRV Return |
3 | PRV 4-7 Return | PRV Return |
4 | + Battery | Battery (+) |
5 | PRV 1-3 Return | PRV Return |
7 | J1939 for CGC | CAN3 + |
8 | Machine Can Data Link | CAN2 + |
9 | J1939 | CAN1 + |
10 | Location Code1 | Switch To Ground 1 |
15 | 5V Supply | 5V Supply 1 |
20 | 8V Supply | 8V Supply 1 |
22 | Hydraulic Lock Solenoid | PRV 1 |
24 | EH - Boom Up | PRV 3 |
26 | J1939 for CGC | CAN3 - |
27 | Machine Can Data Link | CAN2 - |
28 | J1939 | CAN1 - |
29 | Left Joystick Switch 3 | Switch To Ground 8 |
30 | Left Joystick Switch 4 | Switch To Ground 9 |
32 | Pump 1 Displacement Sensor | PWM/Freq In 23 |
33 | Pump 2 Displacement Sensor | PWM/Freq In 24 |
34 | Analog & PWM Return 1 | Analog & PWM return 1 |
35 | Hydraulic Oil Temperature Sensor | Analog Passive In 1 |
37 | Fuel Level Sensor | Fuel Level Sender |
38 | Analog & PWM Return 2 | Analog & PWM return 2 |
41 | Key Switch | Key Switch |
42 | EH - Boom Down | PRV 4 |
43 | EH - Stick Out | PRV 5 |
44 | Ether 2 TX + | Ethernet |
45 | Ether 2 TX - | Ethernet |
46 | Ether 2 RX + | Ethernet |
47 | Ether 2 RX - | Ethernet |
49 | STG Return 1 | STG Return 1 |
50 | Location Code Enable/Disable | Switch To Ground 4 |
52 | Seat Switch | Switch To Ground 6 |
53 | Left Joystick Switch 2 | Switch To Ground 7 |
54 | Pump 1 Pressure Sensor | PWM/Freq In 1 |
55 | Pump 2 Pressure Sensor | PWM/Freq In 2 |
56 | Stick Cylinder Head Pressure Sensor | PWM/Freq In 3 |
57 | Stick Cylinder Rod Pressure Sensor | PWM/Freq In 4 |
58 | Hydraulic Lock Status | Switch To Battery 1 |
59 | Start Detection / Neutral Started Status | Switch To Battery 2 |
60 | Fan Diagnostic | Switch To Battery 3 |
61 | Stick In | PRV 6 |
62 | Bucket Curl | PRV 7 |
63 | Ether 1 TX + | Ethernet |
64 | Ether 1 TX - | Ethernet |
65 | Ether 1 RX + | Ethernet |
66 | Ether 1 RX - | Ethernet |
67 | Capsule Filter Plugged Switch | Switch To Ground 10 |
68 | STG Return 2 | STG Return 2 |
69 | Left Joystick Switch 5 (SVAB) | Switch To Ground 11 |
70 | Right Joystick Switch 5 (SVAB) | Switch To Ground 12 |
71 | Bucket Cylinder End Detection | Switch To Ground 12 |
73 | Boom Cylinder Head Pressure Sensor | PWM/Freq In 5 |
74 | Boom Cylinder Rod Pressure Sensor | PWM/Freq In 6 |
75 | Swing Sensor A | PWM/Freq In 7 |
76 | Swing sensor B | PWM/Freq In 8 |
77 | Bucket Cylinder Head Pressure Sensor | PWM/Freq In 16 |
79 | EH - Bucket Un-curl | PRV 8 |
80 | EH - Swing left | PRV 9 |
81 | EH -Swing Right | PRV 10 |
(1) | Contacts that are not listed are not used. |
Machine ECM #1 Connector J2 Contact Descriptions (1) | ||
---|---|---|
No. | Function | Type |
82 | Right Joystick Switch 1 | Switch To Ground 15 |
83 | Right Joystick Switch 2 | Switch To Ground 16 |
84 | Engine Start Switch (PTS) | Switch To Battery 4 |
85 | Right Joystick Switch 3 | Switch To Ground 17 |
86 | Right Joystick Switch 4 | Switch To Ground 18 |
87 | Analog & PWM Return 4 | Analog & PWM Return 4 |
88 | EP Pump Solenoid 1 | PRV 17 |
89 | EP Pump Solenoid 2 | PRV 18 |
90 | Machine ECM data sharing network (MDTP) | CAN4 + |
91 | Machine ECM data sharing network (MDTP) | CAN4 - |
92 | 8V Supply | 8V Supply 2 |
93 | STG Return 3 | STG Return 3 |
95 | Bucket Cylinder Rod Pressure Sensor | PWM/Freq In 15 |
96 | Bypass Cut 1 | PRV 15 |
97 | Bypass Cut 2 | PRV 16 |
98 | Joystick RH-X | PWM/Freq In 11 |
99 | Joystick RH-Y | PWM/Freq In 12 |
100 | Analog & PWM Return 3 | Analog & PWM Return 3 |
101 | 5V Supply | 5V Supply 2 |
102 | Swing Left Pressure Sensor | PWM/Freq In 13 |
103 | Swing Right Pressure Sensor | PWM/Freq In 14 |
104 | Stick 2 In | PRV 13 |
105 | Stick 2 Cut | PRV 14 |
110 | Joystick LH-X | PWM/Freq In 9 |
111 | Joystick LH-Y | PWM/Freq In 10 |
112 | Boom 2 Up Solenoid | PRV 11 |
113 | Stick 2 Out Solenoid | PRV 12 |
114 | PRV 17-18 Return | PRV 17-18 Return |
117 | PRV 13-14 Return | PRV 13-14 Return |
118 | PRV 15-16 Return | PRV 15-16 Return |
119 | PRV 11-12 Return | PRV 11-12 Return |
(1) | Contacts that are not listed are not used. |
Machine ECM #2 Connector J1 Contact Descriptions (1) | ||
---|---|---|
No. | Function | Type |
1 | Ground | Ground |
2 | PRV 8-10 Return | PRV Return |
3 | PRV 4-7 Return | PRV Return |
4 | + Battery | Battery (+) |
5 | PRV 1-3 Return | PRV Return |
7 | CGC: Can 3 + | CAN3 + |
9 | J1939: Can 1 + | CAN1 + |
11 | Location Code2 | Switch To Ground 2 |
15 | 5V Supply | 5V Supply |
20 | 8V Supply | 8V Supply 1 |
22 | ATT Stem 2 Retract EPRV | PRV 1 |
23 | ATT Stem 2 Extend EPRV | PRV 2 |
24 | ATT Stem 1 Retract EPRV | PRV 3 |
26 | CGC | CAN3 - |
28 | J1939 | CAN1 - |
34 | Analog & PWM Return 1 | Analog & PWM Return 1 |
41 | Key Switch | Key Switch |
42 | Att Stem 2 Extend EPRV | PRV 4 |
43 | Att Stem 3 Retract EPRV | PRV 5 |
44 | Ether 1 TX + | Ethernet |
45 | Ether 1 TX - | Ethernet |
46 | Ether 2 RX + | Ethernet |
47 | Ether 2 RX - | Ethernet |
49 | STG Return 1 | STG Return 1 |
50 | Location Code Enable/Disable | Switch To Ground 4 |
52 | Quick Coupler Switch | Switch To Ground 6 |
54 | CTWT Removal Cylinder Pressure Sensor | PWM/Freq In 1 |
56 | Travel Left Pedal Sensor | PWM/Freq In 3 |
57 | Travel Right Pedal Sensor | PWM/Freq In 4 |
58 | +B for PRV1 power supply | Switch To Battery 1 |
61 | Att Stem 3 Extend EPRV | PRV 6 |
62 | Hydraulic Motor Fan EPRV | PRV 7 |
63 | Ether 1 TX + | Ethernet |
64 | Ether 1 TX - | Ethernet |
65 | Ether 1 RX + | Ethernet |
66 | Ether 1 RX - | Ethernet |
73 | Thumb Wheel 1 - LH | PWM/Freq In 5 |
75 | Thumb Wheel 1 - RH | PWM/Freq In 7 |
79 | Boom 2 Down Solenoid | PRV 8 |
80 | Att Line 1 RERV | PRV 9 |
81 | Att Line 2 RERV | PRV 10 |
(1) | Contacts that are not listed are not used. |
Machine ECM Connector J2 Contact Descriptions (1) | ||
---|---|---|
No. | Function | Type |
87 | Analog & PWM Return 4 | Analog & PWM Return 4 |
88 | EH - Travel Right Fwd | PRV 13 |
89 | EH - Travel Right Rev | PRV 14 |
90 | Machine ECM Data Sharing | CAN4 + |
91 | Machine ECM Date Sharing | CAN4 - |
92 | 8v Supply | 8v Supply |
96 | QCPLR Lock/Unlock Solenoid 2 | PRV 15 |
97 | Travel Left Reverse Solenoid | PRV 12 |
98 | Aux Pedal RH | PWM/Freq In 15 |
99 | Bucket Angle | PWM/Freq in 12 |
104 | QCPLR Lock/Unlock Solenoid 1 | PRV 13 |
105 | Left Travel Forward Solenoid | PRV 11 |
110 | Squeeze Head End Pressure Sensor | PWM/Freq In 9 |
111 | Squeeze Rod End Pressure Sensor | PWM/Freq In 10 |
112 | Swing Brake Solenoid (On/Off) | PRV 11 |
113 | Boom Down Ele Check | PRV 12 |
114 | PRV 17-18 Ret | PRV 17-18 Ret |
117 | PRV 13-14 Ret | PRV 13-14 Ret |
118 | PRV 15-16 Ret | PRV 15-16 Ret |
119 | PRV 11-12 Ret | PRV 11-12 Ret |
(1) | Contacts that are not listed are not used. |
Machine ECM #3 Connector J1 Contact Descriptions (1) | ||
---|---|---|
No. | Function | Type |
1 | Ground | Ground |
3 | PRV 4-7 Return | PRV Return |
4 | + Battery | Battery (+) |
5 | PRV 1-3 Return | PRV Return |
8 | Machine Can Data Link | CAN2 + |
9 | J1939 | CAN1 + |
23 | Fore Boom Extend Solenoid | PRV |
24 | Fore Boom Retract Solenoid | PRV |
27 | Machine Can Data Link | CAN2 - |
28 | J1939 | CAN1 - |
41 | Key Switch | Key Switch |
42 | Boom Coupler Lock Solenoid | PRV |
43 | Boom Coupler Unlock Solenoid | PRV |
48 | STG 3 | Switch To Ground |
50 | STG 4 | Switch To Ground |
58 | STB 1 | Switch To Battery |
61 | Tilt Cab Up Solenoid | PRV |
62 | Tilt Cab Down Solenoid | PRV |
(1) | Contacts that are not listed are not used. |
BCM 1 Connector Contact Descriptions (1) | ||
---|---|---|
No. | Function | Type |
1 | -B | Power Supply |
2 | Driver Return 9-12 | PRV Return |
3 | Driver Return 5-8 | PRV Return |
4 | +B | Power Supply |
5 | Driver Return 1-4 | PRV Return |
8 | J1939 | CAN2 + |
9 | Machine Can Data Link (Local Can) | CAN1 + |
13 | CTWT Removal Switch | CTWT Removal Switch |
14 | CTWT SW UP | CTWT SW UP |
16 | Engine Start Button LED (Green) | Low Current Driver 1 |
17 | Engine Start Button LED (Red) | Low Current Driver 2 |
18 | ECM (Wake Up) | Low Current Driver 3 |
19 | Dome Light / Foot Light | Low Current Driver 4 |
21 | Wake Up Input 1 | Wake up 1 (Switch To Battery) |
22 | Wake Up Input 3 | Wake up 3 (Switch To Ground) |
23 | Main power relay | On/Off Driver / Relay 1 |
24 | M-ECM (Primary) Key Switch | On/Off Driver / Relay 2 |
27 | J1939 | CAN2 - |
28 | Machine Can Data Link (Local Can) | CAN1 - |
29 | Travel Alarm Cancel Switch | Switch To Ground 7 |
30 | Washer Fluid Level Switch | Switch To Ground 8 |
31 | STG Return 7-8 | STG Return 7-8 |
32 | CTWT SW Down | CTWT SW Down |
33 | Beacon Switch | Beacon Switch |
36 | Refuel Pump Relay | Low Current Driver 5 |
37 | Engine Key Switch | Low Current Driver 6 |
38 | Boom Light Relay | Low Current Driver 7 |
39 | Chassis / Cab Light Relay | Low Current Driver 8 |
40 | Wake Up Input 2 | Wake up 2 (Switch To Ground) |
41 | Key Switch (On-Detect) | Key Switch |
42 | Straight Travel Solenoid | On/Off Driver / Relay 3 |
43 | QCPLR Solenoid | On/Off Driver / Relay 4 |
44 | Electric Fan Control 1 | High side PWM output 1 |
45 | Electric Fan Control 2 | High side PWM output 2 |
59 | Heavy Lift Solenoid | On/Off Driver / Relay 5 |
60 | Travel Alarm | On/Off Driver / Relay 6 |
61 | Caution Lamp (for Crane) | On/Off Driver / Relay 7 |
62 | Boom Up Electric Check Solenoid | On/Off Driver / Relay 8 |
63 | Electric Fan Control 3 | High side PWM output 3 |
64 | Seat Belt Caution | On/Off Driver / Relay 9 |
67 | Att Hydraulic Oil Filter Switch | Switch To Ground 5 |
68 | STG Return 5-6 | Switch To Ground Return |
69 | Refuel Start Switch | Switch To Ground 6 |
77 | Key Switch (Off-Detect) | Switch To Battery 8 |
78 | Travel Speed Solenoid | On/Off Driver / Relay 10 |
79 | Fine Swing Solenoid | On/Off Driver / Relay 11 |
80 | Engine Start Signal | On/Off Driver / Relay 12 |
81 | Hydraulic Reverse Fan Solenoid | On/Off Driver / Relay 13 |
(1) | Contacts that are not listed are not used. |
BCM 2 Connector Contact Descriptions (1) | ||
---|---|---|
No. | Function | Type |
1 | -B | Power Supply |
3 | Driver Return 5-8 | PRV Return |
4 | +B | Power Supply |
5 | Driver Return 1-4 | PRV Return |
8 | J1939 | CAN + |
9 | Machine Can Data Link (Local Can) | CAN + |
23 | Sky Wiper relay | On/Off Driver / Relay 1 |
24 | M-ECM (Primary) Key Switch | On/Off Driver / Relay 2 |
27 | J1939 | CAN - |
28 | Machine Can Data Link (Local Can) | CAN - |
41 | Key Switch | Key Switch |
42 | Tilt Cab Alarm | On/Off Driver / Relay 3 |
43 | Free Rotate | On/Off Driver / Relay 4 |
48 | Location Code 3 | Switch To Ground |
49 | STG Return 3-4 | STG Return 3-4 |
50 | Location Code Enable/ Disable | Switch To Ground |
59 | Stability Indicator (Green) | On/Off Driver / Relay 5 |
60 | Stability Indicator (Yellow) | On/Off Driver / Relay 6 |
61 | Stability Indicator (Red) | On/Off Driver / Relay 7 |
(1) | Contacts that are not listed are not used. |