3516B Engine for 994F and 994H Wheel Loaders Caterpillar

Use this procedure to solve communication problems between Caterpillar Electronic Technician (ET) and the Electronic Control Module (ECM). Cat ET must communicate with the ECM in order to fully service the engine.

There is a "Power" indicator on the communication adapter that indicates that the communication adapter is receiving power. An indicator on the communication adapter indicates that communication is occurring on the data link. Cat ET displays a message if Cat ET can not communicate with the data link.

The following conditions can cause a communication problem:

• Cat ET

• Communication adapter and/or cables

• Configuration for the communications adapter

• Electrical power supply to the service tool connector

• Cat Data Link

This procedure determines the root cause of failure to communicate on the data link.

Test Step 1. Verify that the Newest Version of Cat ET is Being Used

Check the version of Cat ET. Cat ET must be the newest version.

Expected Result:

Cat ET is the most current version.

Results:

• OK - Cat ET is the most current version. Attempt to establish communication. Continue with this procedure if the communication adapter does not communicate.

• Not OK - Cat ET is an old version.

  Repair: Download the newest version of Cat ET.

  Attempt to establish communication. Continue with this procedure if the communication adapter does not communicate.

Test Step 2. Verify that the Correct Communication Adapter and Cables are Being Used

Refer to Troubleshooting, "Electronic Service Tools" in order to determine the correct communication adapter and cables.

Expected Result:

The correct communication adapter and cables are used.

Results:

• OK - The correct communication adapter and cables are being used. Attempt to establish communication. Continue with this procedure if the communication adapter does not communicate on the data link.

• Not OK - An incorrect communication adapter or cable was being used.

  Repair: Connect the correct communication adapter or cable. Refer to Troubleshooting, "Electronic Service Tools", if necessary.

  Attempt to establish communication. Continue with this procedure if the communication adapter does not communicate on the data link.

Test Step 3. Verify that Cat ET is Configured Correctly

Cat ET must be configured correctly in order to communicate. Perform the following procedure:

1. Click on the "Utilities" menu.

2. Click on the "Preferences" menu.

3. Select the "Communications" tab.

4. Verify that "Caterpillar Communications Adapter II (Serial IP)" is selected.

   If "Caterpillar Communications Adapter II (Serial IP)" is not an option for selection, the firmware for the communications adapter must be updated. Perform the following procedure:

   Update the communication adapter's firmware by using the "Comm Adapter II Toolkit". Then, select the "Caterpillar Communications Adapter II (Serial IP)" option.

   Continue with this procedure.

5. Check for any hardware that is utilizing the same port as the communications adapter. If any devices are configured to use the same port, exit or close the software programs for that device.

   Note: The most commonly used port is "COM 1".

6. Click "OK".

   Note: Cat ET must reconnect in order for any changes to be used. Electronically disconnect Cat ET if changes were made to any of the settings for communications. Electronically connect Cat ET. Attempt to establish communication. Observe the indicator on the communications adapter.

Expected Result:

Cat ET communicates.

Results:

• OK - Cat ET communicates.

  STOP

• Not OK - Cat ET does not communicate. The "Power" indicator is not illuminated. Proceed to Test Step 4.

• Not OK - Cat ET does not communicate. The "Power" indicator is illuminated. Proceed to Test Step 5.

Test Step 4. Check the Electrical Power to the Communications Adapter

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Illustration 1	g01350067
Power terminals on the service tool connectors. (A) +Battery (B) −Battery

1. Refer to Illustration 1. Check for battery voltage at the service tool connector.

Expected Result:

Battery voltage is not present at the service tool connector.

Results:

• OK - Battery voltage is not present at the service tool connector.

  Repair: Inspect the wiring and fuses. Determine the cause of the missing voltage. Make the necessary repairs.

  Attempt to establish communication after the electrical power is at the service tool connector. Proceed to Test Step 5 if the service tool does not communicate.

• Not OK - Battery voltage is present at the service tool connector.

  Repair: Verify that the cable between the service tool connector and the communication adapter is OK. Replace the cable, if necessary.

  Replace the communication adapter if the following conditions are true:

  • There is power at the cable's "Data Link" connector.

  • The communication adapter's "Power" indicator is not illuminated.

  STOP

Test Step 5. Check the Service Tool Connector

1. Perform a visual inspection of the wiring to the service tool connector. Look for these problems:

   • Harness damage that is caused by chafing

   • Harness damage that is caused by excessive heat

2. Inspect the service tool connector. Pull on each wire that is associated with the data link. This verifies that each wire is properly attached to the terminal and that the terminal is properly inserted into the connector.

   Repair any wiring problems. Attempt to establish communication after the wiring has been repaired.

Expected Result:

The harness for the service tool is OK.

Results:

• OK - The harness for the data link is OK.

  Repair: Refer to Troubleshooting, "Cat Data Link - Test" or refer to Troubleshooting, "CAN Data Link - Test".

  STOP