3406E and 3456 Generator Set Engines Caterpillar

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The connection of any electrical equipment and the disconnection of any electrical equipment may cause an explosion hazard which may result in injury or death. Do not connect any electrical equipment or disconnect any electrical equipment in an explosive atmosphere.

The Electronic Control Module (ECM) contains no moving parts. Replacement of the ECM can be costly. Replacement can also be a time consuming task. Follow the troubleshooting procedures in this manual in order to be sure that replacing the ECM will correct the problem. Verify that the suspect ECM is the cause of the problem.

Note: Ensure that the ECM is receiving power and that the ECM is properly wired to the negative battery circuit before a replacement of the ECM is attempted. Refer to Troubleshooting, "Electrical Power Supply Circuit - Test".

A test ECM can be used to determine if the ECM is faulty. Install a test ECM in place of the suspect ECM. Flash program the correct personality module (flash file) into the test ECM. Program the parameters for normal operation. The parameters must match the parameters in the suspect ECM. Refer to the following test steps for details. If the test ECM resolves the problem, reconnect the suspect ECM. Verify that the problem returns. If the problem returns, replace the ECM.

Note: When a new ECM is not available, you may need to remove an ECM from an engine that is not in service. Ensure that the replacement ECM and the Personality Module Interlock Code match the suspect ECM. Be sure to record the parameters from the replacement ECM on the "Parameters Worksheet". Use the "Copy Configuration/ECM Replacement" feature that is found under the "Service" menu on the Caterpillar Electronic Technician (ET).

Perform the following procedure in order to replace the ECM.

1. Connect Cat ET to the service tool connector for the engine.

2. Print the parameters from the "Configuration" screen on Cat ET. If a printer is unavailable, record all of the parameters. Record any logged diagnostic codes and logged event codes for your records. Record the injector codes from the "Calibrations" screen in the "Service" menu on Cat ET.

   Note: The injector trim code is a number that is found on each of the unit injectors. The ECM uses this number to compensate for manufacturing variations between individual injectors. If you replace any of the unit injectors, you must reprogram the trim code for the new injectors. Also, if you replace the ECM, you must reprogram all of the trim codes.

3. Use the "Copy Configuration/ECM Replacement" feature that is found under the "Service" menu on Cat ET. Select "Load from ECM" in order to copy the configuration from the suspect ECM.

   Note: If the "Copy Configuration" process fails and the parameters were not obtained in Step 2, the parameters must be obtained elsewhere. Some parameters are stamped on the engine information plate, but most parameters must be obtained from the factory.

4. Remove the ECM.

   1. Turn the Engine Control Switch (ECS) to the OFF/RESET position.

   2. Disconnect the ECM connectors J1/P1 and J2/P2.
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      NOTICE
      Use a suitable container to catch any fuel that might spill. Clean up any spilled fuel immediately.

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      NOTICE
      Do not allow dirt to enter the fuel system. Thoroughly clean the area around a fuel system component that will be disconnected. Fit a suitable cover over disconnected fuel system component.

   3. Remove the fuel lines from the ECM.

   4. Remove the mounting bolts from the ECM.

   5. Disconnect the ECM ground strap from the engine.

5. Install the replacement ECM.

   1. Use the old mounting hardware to install the replacement ECM. The mounting hardware should be free of damage.

   2. Reconnect the fuel lines.

   3. Ensure that the ECM mounting hardware is installed correctly. The fuel lines should not be putting tension on the ECM. The rubber grommets are used to protect the ECM from excessive vibration. The ECM should be able to drift in the rubber grommets. If the ECM cannot be moved slightly in the grommets, check that the fuel lines are not pulling the ECM against one side of the grommets.

   4. Install the ECM ground strap on the engine.

   5. Reconnect ECM connectors J1/P1 and J2/P2. Tighten the allen head screws on the connectors to the proper torque:

      • 40-pin connector 2.25 N·m (20 lb in)

6. Flash program the personality module into the ECM. Refer to Troubleshooting, "Flash Programming" for the correct procedure.

7. Use Cat ET to match the engine application and the "Personality Module Interlock Code" if the replacement ECM was used for a different application.

8. Configure the ECM.

   1. If the "Copy Configuration" process from Step 3 was successful, return to the "Copy Configuration/ECM Replacement" screen on Cat ET and select "Program ECM". Proceed to Step 10.

   2. If the "Copy Configuration" process was unsuccessful, program the ECM parameters. The parameters should match the parameters from Step 2.

      Note: If the "Copy Configuration" process fails and the parameters were not obtained in Step 2, the parameters must be obtained elsewhere. Some parameters are stamped on the engine information plate, but most parameters must be obtained from the factory.

   3. If necessary, program the Engine Monitoring System.

9. Calibrate the fuel injectors. Refer to Troubleshooting, "Injector Codes - Calibrate".

10. Calibrate the injection timing. Refer to Troubleshooting, "Engine Speed/Timing Sensor - Calibrate".

11. Check for diagnostic codes and event codes.