3408E and 3412E Engines for Caterpillar Built Machines Caterpillar

The Electronic Control Module (ECM) contains no moving parts. Replacement of the ECM can take a long time. 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 grounded 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. Transfer the personality module from the suspect ECM to 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. The ECM must have the same serial number suffix. 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. Use the "Copy Configuration/ECM Replacement" feature that is found under the "Service" menu on ET.

Perform the following procedure in order to replace the ECM.

1. Connect ET to the service tool connector.

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

3. Use the "Copy Configuration/ECM Replacement" feature that is found under the "Service" menu on 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 keyswitch 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.

   6. If you are flash programming, go to Step 7. If you are physically replacing the personality module, proceed to Step 5.

      Note: Flash programming is the preferred method for replacing the personality module. The personality module can be physically removed, if flash programming is unsuccessful.

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NOTICE
Moisture entry into the ECM from improper servicing can result in ECM failure.

5. Remove the personality module from the old ECM.

   1. Remove the tag wire from the back cover of the ECM.

   2. Remove the bolts from the back cover of the ECM.

   3. Remove the O-ring seal from the cover.

   4. Remove the personality module by squeezing the tabs on the ends of the blue plastic case. Pull the module straight out of the ECM.

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NOTICE
Improper O-ring placement could result in moisture damage from improper sealing. Do not over tighten bolts! This could result in damaged threads and moisture damage from improper sealing.

6. Install the personality module into the replacement ECM.

   1. Carefully seat the personality module in the EPROM carrier socket.

      Note: Do not use excessive force to insert the module into the socket. The socket will accept the personality module in only one position. A click is audible when the personality module is inserted correctly.

   2. Install the O-ring seal for the cover of the personality module.

   3. Install the access cover for the personality module on the ECM. Tighten the cover bolts for the personality module to a torque of 1.36 N·m (12 lb in).

7. 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 pulling 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 a torque of 2.25 N·m (20 lb in).

   6. If the personality module has been physically replaced, go to Step 9. If you are flash programming, continue to Step 8.

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

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

10. Configure the ECM.

    1. If the "Copy Configuration" process from Step 3 was successful, return to the "Copy Configuration/ECM Replacement" screen on ET and select "Program ECM". Proceed to Step 11.

    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.

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

12. Check for diagnostic codes and event codes.