812832 Mercury SCREW POWER TRIM

Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
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 ensure that replacing the ECM will correct the problem and that the 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 you attempt to replace the ECM. Refer to Troubleshooting, "Electrical Power Supply - Test".Note: Do not interchange the master ECM with the alternate ECM in order to determine if an ECM is faulty. If replacement of both modules is necessary, replace the modules one at a time. Transfer the configuration data from one ECM into the Caterpillar Electronic Technician (ET). Replace the suspect ECM and transfer the configuration data from Cat ET into the new ECM. Repeat the process for the alternate ECM. Failure to program each ECM correctly may result in improper engine operation.
If the flash file and engine application are not matched, engine damage may result.
Perform the following procedure in order to replace the ECM:
Print the parameters from the "Configuration" screen on Caterpillar Electronic Technician (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 serial numbers from the "Calibrations" screen under the "Service" menu on Cat ET. Note: The injector serial numbers and the injector confirmation code are necessary for obtaining the correct injector trim files. The injector serial number and the injector confirmation code are located on the injector. The ECM uses the injector trim files in order to compensate for manufacturing variations between individual injectors. If you replace any of the unit injectors, you must reprogram the injector trim files for the new injectors. Also, if you replace the ECM, the injector trim files must be installed into the new ECM. A successful "Copy Configuration" process will accomplish this task. For more instruction, refer to Troubleshooting, "Injector Trim File - Install".
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 1, 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 from the engine.
Remove the electrical power from the ECM.
Disconnect the J1/P1 and J2/P2 ECM connectors.
Use a suitable container to catch any fuel that might spill. Clean up any spilled fuel immediately.
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.
Remove the fuel lines (if equipped) from the ECM.
Remove the mounting bolts from the ECM.
Disconnect the ECM ground strap from the engine.
Install the replacement ECM.
If the old mounting hardware is in good repair, you can use the old mounting hardware to install the replacement ECM.
Reconnect the fuel lines (if equipped).
Ensure that the ECM mounting hardware is installed correctly. The rubber grommets are used to protect the ECM from excessive vibration. The ECM must be able to drift in the rubber grommets. If the installation is equipped with fuel lines, the fuel lines must not put tension on the ECM. 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.
Connect the ECM ground strap.
Connect the J1/P1 and J2/P2 ECM connectors. Tighten the allen head screw on each of the ECM connectors to the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque value.
Install the ECM software. Refer to Troubleshooting, "ECM Software - Install".
If the replacement ECM was used previously for a different application, obtain factory passwords in order to reset the interlock codes.
Configure the ECM.
If the "Load from ECM" process from Step 2 was successful, return to the "Copy Configuration/ECM Replacement" screen on Cat ET and select "Program ECM".After using the "Program ECM" feature, be sure to cycle the power to the ECM. Wait at least 30 seconds after turning the keyswitch to the OFF position.Note: Some control modules have a power off delay. The 30 seconds will be sufficient to cover this delay.
If the "Program ECM" process was successful, proceed to Step 7.d.
If the "Program ECM" process was unsuccessful, manually program the ECM parameters into the replacement ECM. The parameters must match the parameters from Step 1.Note: If the "Copy Configuration" process fails and the parameters were not obtained in Step 1, 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.
If necessary, install the injector trim files. Refer to Troubleshooting, "Injector Trim File - Install".
Check for an active diagnostic code for timing calibration.If the diagnostic code is active, calibrate the injection timing. Refer to calibration procedures Troubleshooting, "Timing - Calibrate".
Check for diagnostic codes and for event codes.