HOUSING 4N9667 - Caterpillar

The Implement ECM determines actions that are based on input information and memory information. After the Implement ECM receives the input information, the ECM sends a corresponding response to the outputs. The inputs and outputs of the Implement ECM are connected to the machine harness by two 70 contact connectors (J1 and J2). The ECM sends the information to the Caterpillar Electronic Technician (Cat ET) on the Cat Data Link.Note: The ECM is not serviceable. The ECM must be replaced if the ECM is damaged. Replace the ECM if a failure is diagnosed.ECM Pull Up Voltage
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. This condition 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 Input switch input circuits
Active analog (voltage) input signal circuits
Passive analog (resistance) input signal circuitsECM Pull Down Voltage
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. This condition 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.Pin Locations
Table 1
Implement ECM Contact Description J1 Contact Descriptions(1)
No.(2) Type Function
10 CAN C Data Link - CAN C Data Link -
11 Sensor Power Output 5V Sensor Supply
13 Battery Return Battery -
20 CAN C Data Link + CAN C Data Link +
21 Sensor Power Return 5V Sensor Return
22 Analog Input Hydraulic Oil Temp Sender Temperature Sensor
23 Battery Return Battery -
31 Battery Power Input Battery +
38 Battery Power Input Battery +
39 Battery Power Input Battery +
47 Battery Power Input Battery +
56 Sensor Power Return 10V Return
57 Battery Return Battery -
69 Sensory Power Output 10V Sensor Supply
70 Battery Return Battery -
(1) Contacts that are not listed are not used.
(2) The connector contacts that are not listed are not used.Inputs
The machine has several different types of input devices. The