BODY 9J8570 - Caterpillar

Test Step 1. INSPECT THE HARNESS CONNECTIONS.
Turn the disconnect switch to the OFF position.
Inspect all of the harness connections. Make sure that the connectors are clean and tight.
Check the connectors for proper mating. Ensure that all the seals are present and in place.
Check the harness for signs of damage or abrasion.
Check the wires at the connector. Ensure that the wires are secured tightly into the connector. Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit. Take care not to pull the wire out of the connector.
Check the exposed wires at the connectors for nicks or signs of abrasion.
Check for moisture inside the connector.
Check the connectors for dirty contacts or corroded contacts.
Check each pin and each socket of the machine harness connectors. Ensure that the contacts are properly installed. The contacts should mate correctly when the two pieces of the connector are placed together. Note: See Testing and Adjusting, "Electrical Connector - Inspect" for more information.Expected Result:The machine harness connectors are tight and free of corrosion. Results:
OK - The machine harness connectors are tight and free of corrosion. Proceed to Test Step 2.
NOT OK - The machine harness connectors are in need of repair.Repair: Repair the machine harness or replace the machine harness. Proceed to Test Step 7.Test Step 2. CHECK THE VOLTAGE OF THE DATA LINK.
Turn the keyswitch and the disconnect switch to the ON position.
Connect CAT ET and verify which ECM has communication diagnostics activated. At each of the ECMs or devices that are not communicating, use an electrical spoon to measure the voltage. One at a time, measure the voltage of connector contact J1-67, J1-68, and J1-69 to frame ground. Note: Do not use the shield wire as a ground.
Table 1
J1-67 J1-68 J1-69
0.5V to 4.5V 0.5V to 4.5V 0V Expected Result:The shield wire does not have a voltage. A voltage on the shield wire means that there is a short to the battery. The voltage of the wires for the Data Link is correct.Results:
OK - The voltages of the wires for the Data Links are correct. Proceed to Test Step 5.
NOT OK - The voltage is greater than 4.5 V.Repair: Repair the machine harness or replace the harness.Proceed to Test Step 7.
NOT OK - The voltage is less than 0.5 V. Proceed to Test Step 3.Test Step 3. CHECK FOR A SHORT TO GROUND.
Turn the keyswitch and the disconnect switch to the OFF position.
Disconnect the J1 harness connector for one of the ECMs. Disconnect the harness connector for the shift pad.
Measure the resistance of wire (F711-YL(Yellow)) to an unpainted frame ground. Measure the resistance of wire (F712-GN(Green)) to an unpainted frame ground. Expected Result:The resistance measurement is greater than 5000 ohms.Results:
OK - The resistance measurement is correct. Proceed to Test Step 4.
NOT OK - The resistance measurement is not correct. The wire with the low resistance measurement is shorted to ground.Repair: Repair the machine harness or replace the machine harness.Proceed to Test Step 7.Test Step