5033722 JOHNSON THERMOSTAT (71.C)

Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Engine ECM
The engine is equipped with an Electronic Control Module (ECM). The ECM contains no moving parts. Follow the troubleshooting procedures in this manual in order to be sure that replacing the ECM will correct a fault. Verify that the suspect ECM is the cause of the fault.Note: Ensure that the ECM is receiving power and that the ECM is properly grounded before replacement of the ECM is attempted. Refer to the schematic diagram.A test ECM can be used in order to determine if the ECM on the engine is faulty. Install a test ECM in place of the suspect ECM. Install the flash file with the correct part number into the test ECM. Program the parameters for the test ECM. The parameters must match the parameters in the suspect ECM. Refer to the following test steps for details. If the test ECM resolves the fault, reconnect the suspect ECM. Verify that the fault returns. If the fault returns, replace the ECM.Note: If an ECM is used as a test ECM, select "Test ECM Mode" on the electronic service tool before the engine serial number is entered.Use the electronic service tool to read the parameters in the suspect ECM. Record the parameters in the suspect ECM. Install the flash file into the new ECM. After the ECM is installed on the engine, the parameters must be programmed into the new ECM.Note: When a new ECM is not available, an ECM can be used from an engine that is not in service. The ECM must have the same serial number suffix. Ensure that the replacement ECM and the part number for the flash file match the suspect ECM. Be sure to record the parameters from the replacement ECM. Use the "Copy Configuration ECM Replacement" function in the electronic service tool.
If the flash file and engine application are not matched, engine damage may result.
Perform the following procedure in order to replace the ECM.
Connect the electronic service tool to the diagnostic connector.
Use the "Copy Configuration ECM Replacement" function from the electronic service tool. If the "Copy Configuration" is successful, proceed to Step 4. If the "Copy Configuration" failed, proceed to Step 10.b. Note: Record any Logged Faults and Events for your records.
Record the following parameters:
Record all of the parameters on the "Configuration" screen.
Record all of the parameters on the "Throttle Configuration" screen.
Record all of the parameters on the "Mode Configuration" screen.
Record the serial numbers of the electronic unit injectors. The injector serial numbers are shown on the "Injector Trim Calibration" screen.Note: If the parameters cannot be read, the parameters must be obtained elsewhere. Some parameters are stamped on the engine information plate, but most parameters must be obtained from the TMI data on SIS Web.
Remove power from the ECM.
Remove the ECM. Refer to Disassembly and Assembly, "Electronic Control Module - Remove and Install".
Install the replacement ECM. Refer to Disassembly and Assembly, "Electronic Control Module - Remove and Install".
If the replacement ECM is used as a test ECM, select "Test ECM Mode" on the electronic service tool.
Download the flash file.
Connect the electronic service tool to the diagnostic connector.
Select "WinFlash" from the "Utilities" menu of the electronic service tool.
Select the downloaded flash file.
If necessary, use the electronic service tool to clear the rating interlock. To clear the rating interlock, enter the factory password when the electronic service tool is first connected. Activating the Test ECM mode will also clear the rating interlock.
Use the electronic service tool to program the parameters. Perform the following procedure.
If the "Copy Configuration" procedure was successful, use the "Copy Configuration, ECM Replacement" function to load the configuration file into the ECM. Note: During the following procedure, factory passwords may be required.
If the "Copy Configuration" procedure failed, configure the parameters individually. The parameters should match the parameters from step 3. Perform the "High Pressure Fuel Pump Calibration".
Check for logged diagnostic codes. Factory passwords are required to clear logged events. Diesel Exhaust Fluid Control Unit (DCU)
Replacement of the DCU does not require the configuration data to be recorded. When the DCU is replaced, the flash file is already installed in the new DCU.DCU - Remove
Turn the keyswitch to the OFF position.
Disconnect the 86 and 53 pin connectors.
Remove the mounting hardware.
Remove the DCU. DCU - Install
Position the DCU on the Pump, Electronics, and Tank Unit (PETU).
Install the previously removed mounting hardware to the replacement DCU. Tighten bolts to a torque of 10 N m (89 lb in).
Connect the 86 and 53 pin connectors.