C175 Tier 4 Final Engines for Off-Highway Trucks Caterpillar

The engine Electronic Control Module (ECM), Aftertreatment ECM, and DCU contain no moving parts. Replacement of the components can be costly. Replacement can also be a time consuming task. Follow the troubleshooting procedures in this manual to ensure that replacing the component will correct the problem. Verify that the suspect component is the cause of the problem.

A test ECM can be used to determine if the ECM is faulty. Refer to Troubleshooting, "Test ECM Mode".

A5:E4 Engine ECM and A5:E2 Aftertreatment ECM Replacement

Perform the following procedure to replace the A5:E4 Engine ECM and A5:E2 Aftertreatment ECM.

1. Record the configuration data.

   1. Try to establish communication between the Cat^® Electronic Technician (ET) and the ECM. Proceed to Test Step 2 if Cat ET does not communicate with the ECM.

   2. Print the parameters from the "Configuration" screen on Cat ET. If a printer is unavailable, record all the parameters.

   3. Obtain the customer passwords from the vehicle owner. Access the customer specified parameters with Cat ET. Record the value of each customer parameter.

      • Record ECM lifetime totals.________

      • Record any logged diagnostic codes. ________

      Note: If the customer passwords are not available, proceed to Troubleshooting, "Customer Passwords" for details that are related to customer passwords.

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

      Note: If the "Copy Configuration" process fails, the parameters must be obtained elsewhere. Some of the system configuration parameters are stamped on the engine information plate. The aftertreatment identification information is stamped on the CEM identification plate. Most of the parameters must be obtained from the factory. Parameters that are related to customer specified parameters must be obtained from the customer or from the Original Equipment Manufacturer (OEM).

2. Removal of the ECM:

   1. Turn the keyswitch OFF.

   2. Disconnect both ECM connectors.

   3. Disconnect the ECM ground strap.

   4. Remove the mounting hardware at each corner of the ECM.

3. Installation of the replacement ECM:

   1. Use the old mounting hardware to install the replacement ECM.

   2. Connect the ECM ground strap.

   3. Connect both ECM connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.

4. Configure the replacement ECM:

   1. Flash program the latest available flash file into the ECM. Refer to Troubleshooting, "ECM Software - Install" for the correct procedure.

   2. Use Cat ET to match the engine application and the interlock code if the replacement ECM was used for a different application.

      Note: Two sets of factory passwords are required to program the Aftertreatment parameters.

   3. If the "Copy Configuration" process from Step 1.d was successful, return to the "Copy Configuration/ECM Replacement" screen on Cat ET and select "Program ECM". Proceed to Step 4.e when programming is complete.

   4. If the "Copy Configuration" process from Step 1.d was unsuccessful, manually program the ECM parameters. The parameters must match the parameters from Step 1.d.

   5. Program the engine monitoring system, if necessary.

Diesel Exhaust Fluid Control Unit (DCU) Replacement

Replacement of the DCU does not require the configuration data to be recorded.

1. Removal of the DCU:

   1. Turn the keyswitch to the OFF position.

   2. Disconnect the 86 and 53-pin connectors.

   3. Remove the mounting hardware.

2. Installation of the replacement DCU:

   1. Install the previously removed mounting hardware to the replacement DCU.

   2. Connect the 86 and 53-pin connectors.

   3. Turn the keyswitch to the ON position.

   4. Connect Cat ET.

   5. Flash program the latest available flash file into the DCU. Refer to Troubleshooting, ECM Software - Install for the correct procedure.

Additional Procedures when Replacing the Engine, Engine ECM, Aftertreatment ECM, DCU, or CEM

CEM Replacement without an Engine Replacement

1. If the CEM was replaced, reset the Selective Catalyst Reduction (SCR) catalyst aging model by performing the "Aftertreatment #X SCR Catalyst Replacement" in Cat ET. The feature must be reset to guarantee that the Diesel Exhaust Fluid (DEF) dosing system doses the correct amount of DEF into the aftertreatment system.

2. Update the CEM serial number with Cat ET.

   1. Click "Configuration".

   2. Select "Selective Catalyst Reduction System".

   3. Select "Factory Installed Aftertreatment #1 Indentification Number".

   4. Click the "Change" tab at the bottom of the screen.

   5. Type in the new CEM serial number and click "OK".

3. Perform an "Aftertreatment System Functional Test" in Cat ET to verify the correct operation of the new CEM.

4. Report both the old CEM serial number and the new CEM serial number in the SIMSi service report.