MULTIMETER G- 6V7800 - Caterpillar

Table 1
Location Codes for the Transmission ECM    
Hardware Location Code     ECM    Pin Number    
ET Location Code     13     -    
LOC 0     Open     J1-20    
LOC 1     Ground     J1-21    
LOC 2     Open     J1-22    
LOC 3     Open     J1-23    Expected Result:The resistance that is measured is greater than 5000 ohms at contacts J1-21, J1-22, and J1-23. The resistance measures less than 5 ohms at contact J1-20.Results:
OK - The resistance that is measured is greater than 5000 ohms at contacts J1-21, J1-22, and J1-23. The resistance measures less than 5 ohms at contact J1-20. The harness circuit is correct. Proceed to test step 5.
NOT OK - One or more of the resistance measurements is NOT correct. The machine harness has failed.Repair: Repair the machine harness or replace the machine harness. Stop.Test Step 5. CHECK FOR SHORTS TO THE +BATTERY CIRCUIT.
The disconnect switch remains OFF.
The ECM remains disconnected from the machine harness connector.
At the machine harness connector for the ECM, measure the resistance between J1-20 and all possible sources of the +battery circuit.
Table 2
Location Codes for the Transmission ECM    
Hardware Location Code     ECM    Pin Number    
ET Location Code     13     -    
LOC 0     Open     J1-20    
LOC 1     Ground     J1-21    
LOC 2     Open     J1-22    
LOC 3     Open     J1-23    Expected Result:The resistance is greater than 5000 ohms.Results:
OK - The resistance is greater than 5000 ohms. The harness circuit is correct. Proceed to test step 6.
NOT OK - The resistance is less than 5000 ohms. The machine harness has failed.Repair: Repair the machine harness or replace the machine harness. Stop.Test Step 6. CHECK FOR AN OPEN HARNESS.
The disconnect switch remains in the OFF position.
The ECM remains disconnected from the machine harness.
At the machine harness for the ECM, measure the resistance between the frame ground and J1-20.Expected Result:The resistance is less than 5 ohms.Results:
OK - The resistance is less than 5 ohms. The location code circuit is correct. The ECM has failed.Repair: It is unlikely that the ECM has failed. Exit this procedure and perform this diagnostic code procedure again. If the cause of the diagnostic code is not found replace the ECM. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace". Stop.
NOT OK - The resistance is greater than 5 ohms. The machine harness has failed.Repair: Repair the machine harness or replace the machine harness. Stop.