725, 730, 735, 740 and 740 EJECTOR Articulated Trucks Power Train Electronic Control System Caterpillar

This diagnostic code is recorded when the software location code for the transmission/chassis ECM does not match the hardware location codes.

The probable cause of this diagnostic code is software. The wrong software has been flashed into the ECM.

Note: Do not change the hard wired location code if you have flashed the incorrect software into the control.

Test Step 1. VERIFY HARDWARE AND SOFTWARE PART NUMBERS

1. Verify whether the part number of the software for the ECM is correct.

Expected Result:

Consult the Business Unit that is producing the product for the correct configuration for the machine.

Results:

• OK - All part numbers are correct for the ECM. Proceed to test step 2.

• NOT OK - All part numbers are NOT correct. The installed ECM has the wrong part number or incorrect configuration software is installed.

  Repair: Replace the ECM with a module that has the correct part number or flash the correct configuration software. See Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program".

  Stop.

Test Step 2. VERIFY WHETHER THE LOCATION CODE MATCHES THE ET STATUS SCREEN.

1. Check the ET status screen in order to verify the location code .

Expected Result:

The location codes in the ET are correct.

Results:

• OK - The location codes in the ET are correct. Proceed to test step 3.

• NOT OK - The location codes are NOT correct.

  Repair: Repeat this test step in order to verify that the software and hardware part numbers are correct.

  Proceed to test step 3 if the part numbers are correct.

Test Step 3. INSPECT HARNESS CONNECTIONS

1. Turn the key start switch and the disconnect switch to the OFF position.

2. Inspect the harness connections that are related to the location codes. Make sure that the connectors are clean. Make sure that the connectors are tight.

3. Check for the proper mating of the connector.

4. Check all wires at the connector.

5. Check each wire for nicks. Check each wire for signs of abrasion in the insulation.

6. Check for moisture at the connector.

7. Check for dirty contacts or corroded contacts.

8. Check each pin and check each socket.

Expected Result:

The machine harness connectors are tight and the machine harness connectors are free of corrosion.

Results:

• OK - The machine harness connectors are tight and the machine harness connectors are free from corrosion. Proceed to test step 4.

• NOT OK - One or more of the machine harness connectors are in need of repair.

  Repair: Repair the machine harness or replace the machine harness.

  Stop.

Test Step 4. CHECK FOR SHORTS TO GROUND.

1. The disconnect switch and the key start switch remain in the OFF position.

2. Disconnect the machine harness connector from the ECM.

3. At the machine harness for the ECM, measure the resistance between the frame ground and the location code pins.
   Show/hide table

   Table 1

   Location Codes for the Transmission/Chassis ECM
   Hardware Location Code	ECM	Pin Number
   ET Location Code	14	-
   LOC 0	Ground	J1-20
   LOC 1	Open	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.

1. The disconnect switch remains OFF.

2. The ECM remains disconnected from the machine harness connector.

3. At the machine harness connector for the ECM, measure the resistance between J1-20 and all possible sources of the +battery circuit. The possible sources of positive voltage are contacts: 725 and 730 machines J1-11, J1-58, J2-1, J2-15, J2-16, J2-17, J2-23, J2-25, J1-39, J2-40, J2-44, J2-45, J2-47, J2-51, J2-57, J2-58, J2-60, J2-62, J2-63, J2-64, J2-65, J2-68 and J2-70. 735 machines J1-11, J1-58, J2-1, J2-14, J2-15, J2-16, J2-17, J2-23, J2-25, J1-39, J2-40, J2-44, J2-45, J2-47, J2-51, J2-57, J2-58, J2-60, J2-61, J2-62, J2-63, J2-64, J2-65, J2-68 and J2-70. 740 machines J1-11, J1-58, J2-1, J2-14, J2-15, J2-16, J2-17, J2-23, J2-25, J1-39, J2-40, J2-44, J2-45, J2-47, J2-55, J2-57, J2-58, J2-60, J2-68 and J2-70.

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.

1. The disconnect switch remains in the OFF position.

2. The ECM remains disconnected from the machine harness.

3. 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.