AD30 and AD55 Underground Articulated Trucks Power Train Electronic Control System Caterpillar

Illustration 1	g01057183
Schematic of the CAT Data Link circuit.

This diagnostic code is associated with the information sent from the Engine Electronic Control Module (Engine ECM) to the Power Train/Chassis Electronic Control Module (Power Train/Chassis ECM). The information is sent via the CAT Data Link. The CAT Data Link is connected to two inputs of the Power Train/Chassis ECM.

The FMI 12 means that the Power Train/Chassis ECM has not received expected information from the Engine ECM.

The possible causes of this diagnostic code are listed below:

• The wires for the CAT Data Link to the Engine ECM are open or the wires are shorted.

• The wrong software is installed on an ECM.

• An ECM has the wrong part number.

Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0590 FMI 12 is active before performing this procedure.

Test Step 1. VERIFY THE HARDWARE AND THE SOFTWARE PART NUMBERS

1. Verify that the following information is correct:

   • The part number of the flash software for the Engine ECM.

   • The part number of the Engine ECM.

   • The part number of the flash software for the Power Train/Chassis ECM.

   • The part number of the Power Train/Chassis ECM.

   Note: Consult your Caterpillar dealer for the correct part numbers of the flash software.

Expected Result:

All the part numbers are correct.

Results:

• OK - All the part numbers are correct. Proceed to Test Step 2.

• NOT OK - Any or all the part numbers are not correct.

  Repair: The incorrect flash software is installed to the Engine ECM or the Power Train/Chasis ECM. Install the correct flash softwear to the ECM.

  The Engine ECM or the Power Train/Chassis ECM have the incorrect part number. Replace the Engine ECM or replace the Power Train/Chassis ECM that is incorrect.

  STOP

Test Step 2. INSPECT THE HARNESS CONNECTIONS

1. Turn the battery disconnect switch to the OFF position.

2. Inspect all harness connections that are related to the CAT Data Link. Make sure that the connectors are clean and tight.

3. Ensure that each connector properly locked into the connector body. Ensure that all the seals are present and in place.

4. Check the harness for signs of damage or abrasion.

5. Check the wires at the connector. Ensure that the wires are secured tightly into the connector. Take care not to pull the wire out of the connector.

6. Check the exposed wires at the connectors for nicks or signs of abrasion.

7. Check for moisture inside the connector.

8. Check the connectors for dirty contacts or corroded contacts.

9. 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.

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 3.

• NOT OK - The machine harness connectors are in need of repair.

  Repair: Repair the machine harness and/or the connector or replace the machine harness and/or the connector.

  STOP

Test Step 3. CHECK FOR SHORTS TO GROUND

1. The battery disconnect switch remains in the OFF position.

2. Disconnect the machine harness from all electronic control modules that use the CAT Data Link.

3. At the machine harness for the Power Train/Chassis ECM, measure the resistance between contacts J1-9 (wire 893-GN(Green)) and J1-3 (wire 892-BR(Brown)) of the CAT Data Link and frame ground.

Expected Result:

The resistance is greater than 5 ohms.

Results:

• OK - The resistance is greater than 5 ohms. The harness circuit resistance is correct. Proceed to Test Step 4.

• NOT OK - The resistance is less than 5 ohms. The machine harness has failed.

  Repair: There is a short between frame ground and the CAT Data Link circuit in the machine harness. Repair the machine harness or replace the machine harness.

  STOP

Test Step 4. CHECK THE MACHINE HARNESS FOR A SHORT TO THE +BATTERY CIRCUIT

1. The battery disconnect switch remains in the OFF position.

2. All related electronic control modules remain disconnected from the machine harness.

3. At the machine harness connector for the Power Train/Chassis ECM measure the resistance between the connector contact J1-1 (wire 126-PK(Pink)) and connector contact J1-9 (wire 893-GN(Green)).

4. At the machine harness connector for the Power Train/Chassis ECM measure the resistance between the connector contact J1-1 (wire 126-PK(Pink)) and connector contact J1-3 (wire 892-BR(Brown)).

Expected Result:

The resistance is greater than 5 ohms.

Results:

• OK - The harness circuit resistance is correct. Proceed to Test Step 5.

• NOT OK - The resistance is less than 5 ohms. The machine harness has failed.

  Repair: There is a short between the +battery circuit and the circuits of the CAT Data Link circuit in the machine harness. Repair the machine harness or replace the machine harness.

  STOP

Test Step 5. CHECK FOR OPEN HARNESS

1. The battery disconnect switch remains in the OFF position.

2. All related electronic control modules remain disconnected from the machine harness.

3. Measure the resistance between connector contact J1-9 (wire 893-GN(Green)) of the Power Train/Chassis ECM and connector contact J1-8 (wire 893-GN(Green)) of the Engine ECM.

4. Measure the resistance between connector contact J1-3 (wire 892-BR(Brown)) of the Power Train/Chassis ECM and connector contact J1-9 (wire 892-BR(Brown)) of the Engine ECM.

Expected Result:

The resistance measures less than 5 ohms.

Results:

• OK - The resistance is less than 5 ohms. The CAT Data Link circuit in the machine harness is correct. Proceed to Test Step 6.

• NOT OK - The resistance is greater than 5 ohms. The machine harness has failed.

  Repair: The CAT Data Link circuit is open in the machine harness. Repair the machine harness or replace the machine harness.

  STOP

Test Step 6. CHECK IF THE DIAGNOSTIC CODE REMAINS

1. Inspect the contacts of the harness connectors and clean the contacts.

2. Reconnect all harness connectors.

3. Turn the battery disconnect switch and the key start switch to the ON position.

4. Operate the machine.

5. Check the status of the CID 0590 FMI 12.

Expected Result:

The CID 0590 FMI 12 is active.

Results:

• YES - The CID 0590 FMI 12 is active. The diagnostic code has not been corrected. The Power Train/Chassis ECM may have failed.

  Repair: It is unlikely that the Power Train/Chassis ECM has failed. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the Power Train/Chassis ECM. Refer to Systems Operation, Troubleshooting, Testing and Adjusting, "Electronic Control Module (ECM) - Replace" for the machine that is being serviced.

  STOP

• NO - The CID 0590 FMI 12 is not active. The diagnostic code does not exist at this time.

  Repair: The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation.

  STOP