259D Compact Track Loader – Electronic Control Module (ECM) – Replace

Prior to replacement of the ECM, ensure that replacement of the ECM is absolutely necessary. The ECM is seldom the cause of an active diagnostic code. Verify that all possible causes of the problem have been investigated. Always check that the proper ground and power is available to the ECM. Before replacing the ECM, contact your Caterpillar dealership's Technical Communicator for possible consultation with Caterpillar.

Note: New electronic control modules are available either pre-programmed for a particular machine or the ECM is not programmed. An ECM that has not been programmed must be programmed by using the Caterpillar Electronic Technician (Cat ET). See Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program". See step 8 in order to determine whether the ECM has been programmed.

The following "Replacement Procedure For An ECM That Is Communicating" procedure is for replacement of an ECM that is capable of communicating with Cat ET. This procedure can be performed for replacement of most ECM controls on most Caterpillar machine models.

For replacement of a ECM that will not communicate with Cat ET or will not save the configuration data to file, proceed to the "Replacement Procedure For A ECM That Is Not Communicating" procedure below.

Replacement Procedure For An ECM That Is Communicating

1. Save the ECM configuration data. Go to the help screen that is shown in illustration 1, and follow the instruction in order to save the configuration data to a file. This file will be used in order to load the configuration data to the new ECM.

2. Turn the key start switch to the OFF position.

3. Disconnect the machine harness from the ECM.

4. Remove the ECM.

5. Ensure that the replacement ECM has the correct part number.

6. Connect the machine harness to the ECM.

Note: Two key start ON/OFF cycles are required for correct initialization of the new ECM.

7. Turn the key start switch to the ON position. Wait for a minute to let the ECM initialize. Turn the key start switch to the OFF position. Wait 10 seconds. Turn the key start switch to the ON position a second time for correct initialization of the ECM.

8. Determine whether the ECM has been programmed. Connect the (Cat ET) to the service tool connector. Cat ET communicates with the ECM.

   Cat ET will indicate whether the ECM has been programmed. An ECM that has not been programmed must be programmed by using the WinFlash software which is contained in Cat ET. See Troubleshooting, "Electronic Control Module (ECM) - Flash Program".

   Cat ET will provide access to the ECM if the ECM has already been programmed.

9. Using the Cat ET service tool, select the "Service" function from the drop-down menu. Then, select the "Configuration" function. A list of items will appear. Each item in this list should be checked in order to verify that the setting matches the machine configuration. The following information is an example of what might be viewed in order to verify the proper machine configuration. Select "Ride Control System Installation Status" from the choices. Select the "change" button. Select "Installed" or "Not Installed".

10. The following information is another example of what might be viewed in order to verify the proper machine configuration. Select the "Service" function from the Cat ET. Select "Configuration" from the choices. A list of items will appear. From the list, select "Engine Fan Control". Select the "change" button. Select "On" or "Off".

11. Perform all applicable system calibrations. See the Testing and Adjusting, "Calibration" procedure in the service manual for your machine.

Note: Some variations in Cat ET menu may be experienced. View the proper subject for information about a specific Cat ET menu.

Note: Performance will be affected by ANY calibration procedures that are omitted. Make sure that all calibration procedures are performed. Perform all calibration procedures, even if the replacement ECM was acquired from a similar machine.

Replacement Procedure For A ECM That Is Not Communicating

This procedure should be performed for a ECM that will not communicate with Cat ET or will not save the configuration data to a file.

Prior to replacement of the ECM, ensure that replacement of the ECM is absolutely necessary. The ECM is seldom the cause of an active diagnostic code. Verify that all possible causes of the problem have been investigated. Always check that the proper ground and power is available to the ECM. Before replacing the ECM, contact your Caterpillar dealership's Technical Communicator for possible consultation with Caterpillar.

Note: The first steps will verify that the Cat Data Link circuit between the service connector and the ECM that being replaced is not causing the communication problem.

1. Disconnect the negative battery cable and turn the key start switch to the OFF position.

2. Disconnect the machine harness J1 connector from the ECM that is being replaced.

3. Using the diagram for the Cat Data Link connections, connect a jumper wire between the data link (+) contact (wire 893-GN) and the data link (-) contact (wire 892-BR).

4. At the service connector, measure the resistance between data link (+) contact D (wire 893-GN) and data link (-) contact E (wire 892-BR).

   Result: The resistance measurement should be less than 5.0 ohms.

   If the resistance measurement is greater than 5.0 ohms, there is an open or a poor connection in the Cat Data Link circuit. Refer to the complete machine Electrical System Schematic for your machine. Check the data link circuit for opens or bad connections. Repair the data link circuit and then try to establish communication with the ECM. If the ECM still will not communicate, proceed to the next step.

   If the resistance measurement is less than 5.0 ohms, proceed to the next step.

5. Disconnect the machine harness connector J2 from the ECM.

6. Remove the ECM.

7. Ensure that the replacement ECM has the correct part number.

8. Connect the machine harness to the ECM.

Note: Two key start ON/OFF cycles are required for correct initialization of the new Implement ECM.

9. Reconnect the negative battery cable and turn the key start switch to the ON position. Wait for a minute to let the ECM initialize. Turn the key start switch to the OFF position. Wait 10 seconds. Turn the key start switch to the ON position a second time for correct initialization of the ECM.

10. Determine whether the ECM has been programmed. Connect the (Cat ET) to the service tool connector. Cat ET communicates with the ECM.

    Cat ET will indicate whether the ECM has been programmed. An ECM that has not been programmed must be programmed by using the WinFlash software which is contained in Cat ET. See Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program".

    Cat ET will provide access to the ECM if the ECM has already been programmed.

The ECM should now be operational. The machine operating parameters that can be configured will be set to the factory default settings when the software is flashed to the ECM.

Check all of the machine systems for proper operation before operating the machine.

Note: For a listing of the parameters that can be configured in the ECM, refer to the Testing and Adjusting, "Electronic Control Module (ECM) - Configure" section of this manual.