C9.3 Marine Auxiliary and Generator Set Engine Caterpillar

Download the "Warranty Report" from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes. Check Caterpillar ^® Electronic Technician (Cat ET) for any associated codes that are listed in Table 1. Troubleshoot any active codes before continuing with this procedure.

Table 1

Associated Diagnostic Trouble Codes

157-17

5580-18

5584-15

5584-16

Probable Causes

• Codes

• Parameters

• Throttle Signal

• Inlet air restriction

• Exhaust restriction

• Fuel System

• Engine Load

• Valve Lash

Recommended Actions

Note: The procedures have been listed in order of probability. Complete the procedures in order.

Note: If the problem only occurs under certain conditions, test the engine under those conditions. Examples of certain conditions are high engine speed, full load, and engine operating temperature. Troubleshooting the symptoms under other conditions can give misleading results.

Table 2

Troubleshooting Test Steps	Values	Results
1. Engine Derate or Active Codes A. Certain diagnostic codes and/or event codes may cause poor performance. Refer to the histogram information for engine derates in Cat ET. Check for the following histograms: 1. High Exhaust Temperature Prevention Derate Time Histogram 2. High Turbo Speed Prevention Derate Time Histogram B. If the histograms contain derates and no diagnostic codes are present, then the engine is operating normally. The following list contains conditions that can cause derates: 1. Elevated altitude 2. Elevated inlet air temperature 3. Elevated ambient temperature	Engine Derate or Active Codes	Result: A diagnostic code is present. Repair: Troubleshoot the code and then reset the histogram. Result: A diagnostic code is not present. Proceed to Test Step 2.
2. Check for Incorrect Configuration Parameters A. Connect Cat ET to the service tool connector. verify that the correct parameters are being used. B. Use Cat ET to verify that the correct parameters are being used.	Parameters	Result: The parameters are correct. Proceed to Test Step 3. Result: The parameters are not correct. Repair: Input the correct parameters. Refer to Troubleshooting, "Configuration Parameters" for additional information. If the problem is not resolved, proceed to Test Step 3.
3. Check the Throttle Signal A. Monitor the status for "Throttle Position" on Cat ET. Verify that the status for "Throttle Position" is stable and that the engine is able to reach high idle speed.	Throttle Signal	Result: The throttle signal is stable. Proceed to Test Step 4. Result: The throttle signal is not stable. Repair: Make the necessary repairs, Refer to the appropriate circuit test. If the problem is not resolved, proceed to Test Step 4.
4. Check for Restriction in the Air Inlet System A. Check for an air filter restriction indicator. Refer to the Operation and Maintenance Manual for additional information. B. Measure the inlet air restriction for the turbocharger. Refer to Troubleshooting, "Inlet Air Is Restricted" for additional information.	Restrictions	Result: The inlet air restriction is OK. Proceed to Test Step 5. Result: The inlet air restriction is NOT OK. An imbalance in the system is discovered. Repair: Repair or replace damaged inlet air system components. Equalize the inlet air restriction for the turbocharger. If the problem is not resolved, proceed to Test Step 5.
5. Check for a Restriction in the Exhaust System A. Measure the exhaust restriction during engine operation with a load. For data that is specific to your engine, refer to the Technical Marketing Information (TMI).	Restrictions	Result: The exhaust restriction measurement is OK. Proceed to Test Step 6. Result: The exhaust restrictions not OK. Repair: Repair or replace damaged exhaust system components. If the problem is not resolved, proceed to Test Step 6.
6. Inspect the Fuel System Refer to Systems Operation/Testing and Adjusting, "Fuel System Inspection" for additional information. A. Visually check the fuel level in the fuel tank. Do not rely on the fuel gauge only. B. Ensure that the vent in the fuel cap is not filled with debris. C. Ensure that the fuel supply valve (if equipped) is in the full OPEN position. Note: Cold weather adversely affects the characteristics of the fuel. Refer to the engines Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold-weather operation. Cold mode (if applicable) is activated whenever the engine coolant temperature falls below a predetermined value. Monitor the status screen on Cat ET in order to verify that the engine has exited cold mode. Observe the reading for coolant temperature on the Cat ET. D. Inspect the fuel system. Refer to Systems Operation/Testing and Adjusting, "Fuel System - Inspect" for additional information. F. Check fuel quality. Refer to Systems Operation/Testing and Adjusting, "Fuel Quality - Test" for additional information. Check the fuel tank for debris or foreign objects which may block the fuel supply. G. Check for the proper operation of the fuel transfer pump. Refer to Systems Operation/Testing and Adjusting, "Fuel System" for test information.	Fuel system	Result: The fuel pressure is OK. Proceed to Test Step 7. Result: The fuel pressure is not OK. Repair: Replace the fuel filters. Clean the primary filter/water separator of debris. Refer to the Operation and Maintenance Manual for details. If the problem is not resolved, proceed to Test Step 7.
7. Engine Load A. Check accessories and parasitic loads on the engine.	Engine loads	Result: There is not a parasitic load. Proceed to Test Step 8. Result: There is a parasitic load. Repair: Remove the parasitic load. If the problem is not resolved, proceed to Test Step 8.
8. Check the Valve Lash Note: The valve lash can affect the performance of the engine.	Valve lash	Result: The valve lash is NOT OK. Repair:Reset the valve lash. Refer to Testing and Adjusting, "Engine Valve Lash - Inspect/Adjust" for additional information.

If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).