77327 Mercury MOUNT

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".Perform the following procedure in order to replace the ECM.
Connect Caterpillar Electronic Technician (ET) to the service tool connector for the engine.
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.
Copy the settings for the engine monitoring system. Refer to Troubleshooting, "Event Codes".
Copy the injector trim codes. The injector trim codes are not part of the "Configuration" screen on Caterpillar Electronic Technician (ET). "Injector Codes Calibration" can be found under "Calibrations" 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.
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.b, the parameters must be obtained elsewhere. Some parameters are stamped on the engine information plate, but most parameters must be obtained from the factory.
Remove the ECM.
Turn the battery disconnect switch to the OFF position.
Disconnect the ECM connectors J1/P1 and J2/P2.
Remove the mounting bolts from the ECM.
Disconnect the ECM ground strap from the engine.
Install the replacement ECM.
Use the old mounting hardware to install the replacement ECM. Make sure that the mounting hardware is free of damage. Ensure that the ECM mounting hardware is installed correctly.
The ECM must be able to drift in the rubber grommets.
Install the ECM ground strap on the engine.
Reconnect ECM connectors J1/P1 and J2/P2. Torque the allen head screw for the 70 pin ECM connector. Refer to Troubleshooting, "Inspecting Electrical Connectors" for the correct torque value for your application.
If the flash file and engine application are not matched, engine damage may result.
Flash program the ECM. Refer to Troubleshooting, "Flash Programming" for the correct procedure.
Configure the ECM.
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 9.
If the "Copy Configuration" process was unsuccessful, program the ECM parameters. The parameters must match the parameters from Step 2.b. Note: If the "Copy Configuration" process fails and the parameters were not obtained in Step 2.b, the parameters must be obtained elsewhere. Some parameters are stamped on the engine information plate, but most parameters must be obtained from the factory.
If necessary, program the engine monitoring system. Refer to Troubleshooting, "Event Codes".
Program the injector trim codes.
Calibrate the injection timing. Refer to Troubleshooting, "Engine Speed/Timing Sensor - Calibrate".
Check for diagnostic codes and event codes.