HOUSING ASSEM. 2G9959 - Caterpillar

Test Step 1. CHECK THE DATA LINK CIRCUITS FOR OPEN CIRCUITS
Turn the battery disconnect switch and the key start switch to the OFF position.
At the front of the "Inverter Cabinet", remove the low voltage compartment cover (4).
At the Motor 1 ECM, disconnect the machine harness connector J1. Examine the pins and sockets on the ECM and on the J1 harness connector. Ensure that all the pins and sockets are secured in the connector, the contacts are clean, and the contacts are in good condition. Connect a jumper wire between the CAN A high contact J1-66 and the CAN A low contact J1-67.
At the "VIMS Main" ECM, disconnect the machine harness connector from the ECM. Examine the pins and sockets on the ECM and on the harness connector. Ensure that all the pins and sockets are secured in the connector, the contacts are clean, and the contacts are in good condition.
At the "VIMS Main" ECM, harness connector, measure the resistance between contact 50 (wire Y956-YL(Yellow)) and contact 34 (wire Y957-GN(Green)).
While observing the resistance measurement, wiggle the harness connector for the "VIMS Main" ECM and wiggle the harness connector for the Motor 1 ECM. Do not disconnect the jumper wire. While observing the resistance measurement, individually wiggle the CAN A "Y" connectors, CANA-2 and CANA-1.
At the harness connector J1 for Motor 1 ECM, disconnect the jumper wire from the CAN A high (J1-66) and the CAN A low (J1-67).
At the harness connector J1 for Motor 1 ECM, measure the resistance of the circuits between the CAN A high (J1-66) and the CAN A low (J1-67).Expected Result:The resistance measurement with the jumper wire connected is 5 ohms or less always during the manipulation of the circuit connectors. The resistance measurement with the jumper wire disconnected is approximately 60 ohms.Results:
OK - When the jumper wire is connected, the resistance measurement is 5 ohms or less during the manipulation of the circuit connectors. The "CAN A" data link circuit between the "Motor 1" ECM and the "VIMS Main" ECM is not open or appear to have a poor connection. When the jumper wire is disconnected, the resistance measurement is approximately 60 ohms. The terminal resistors in the circuit are connected and are in good condition. Proceed to Test Step 2.
NOT OK - Either the resistance measurement with the jumper wire connected is greater than 5 ohms or the resistance measurement with the jumper disconnected is not 60 ohms.Repair: If the resistance measurement with the jumper wire connected is greater than 5 ohms, there is an open or a poor connection in the data link circuits between the "VIMS Main" ECM and the "Motor 1" ECM.Refer to the connection diagram at the beginning of this procedure. All the data link connection points between the two ECMs are illustrated in the diagram. Locate and examine all the connections in the circuit. Check each wire at each connection for poor connections or loose connections in the connector. Ensure that all connections are clean, secure, and in