BOOT 2915392 - Caterpillar

Table 2
Associated Diagnostic Trouble Codes    
CDL Code     J1939 Code    
1779-5     1347-5    
1779-6     1347-6    
1780-5     1348-5    
1780-6     1348-6    
1797-3     157-3    
1797-4     157-4    
390-1     614-15    
390-2     614-16    
198-1     5580-17    
198-2     5580-18    Troubleshooting Procedure
Table 3
Troubleshooting Test Steps    Values    Results    
1. Check for Associated Codes
A. Establish communication between Cat® Electronic Technician (ET) and the Engine Electronic Control Module (ECM).
B. Download the "Warranty Report" from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes.
C. If any of the associated codes in Table 2 are logged, troubleshoot the codes before continuing with this procedure.
   
Associated Codes    
Result: An associated code is active or logged.
Repair: Troubleshoot the associated codes before continuing with this procedure.
Result: An associated code is not active or logged.
Proceed to Test Step 2.    
2. Inspect the Fuel System
A. Inspect the fuel system. Refer to Systems Operation/Testing and Adjusting, "Fuel System - Inspect" for inspection of the high-pressure fuel lines and the fuel rail.
   
Fuel System Problems    
Result: Problems were found with the fuel system.
Repair: Repair the components or replace the components that are damaged. Verify that the problem is resolved.
Result: Problems were not found with the fuel system.
Proceed to Test Step 3.
   
3. Check the Fuel Rail Sensor
A. Allow the engine to be OFF for 10 minutes.
B. Turn the keyswitch to the ON position, do not start the engine.
C. Connect to the Engine ECM using Cat ET.
D. Using Cat ET, check the status of the "Fuel Rail Pressure (absolute)".
   
Rail Pressure Less than 5,000 kPa (725 psi)     Result: The pressure dropped below
5,000 kPa (725 psi) after the engine was shut off for 10 minutes.
Proceed to Test Step 4.
Result: The pressure did not drop below
5,000 kPa (725 psi) after the engine was shut off for 10 minutes.
Repair: Replace the fuel rail pressure sensor. If the problem has been corrected, return the unit to service.
   
4. Start the Engine
A. Try to start the engine.
   
Engine     Result: The engine will start.
Proceed to Test Step 5.
Result: The engine will not start.
Repair: Refer to Systems Operations/Testing and Adjusting, "Injector Bypass Fuel Flow"
   
Illustration 1 g03383455
Location of the "Fuel System Functional Test" in the "Diagnostic Service Test" menu
Illustration 2 g03383456
If an E398 Low Fuel Rail Pressure fault is