BEARING 4M9920 - Caterpillar

Use this procedure to troubleshoot abnormal fuel rail pressure or use this procedure if any of the following diagnostic trouble codes are active. Refer to Troubleshooting, "Diagnostic Trouble Codes" for information about the code.
Table 1
Diagnostic Trouble Codes for Fuel Rail Pressure Problem
J1939 Code Code Description Comments
157-15 Engine Injector Metering Rail #1 Pressure: High - least severe (1) No other 157-XX codes are active.
3509-XX codes are not active.
3510-XX codes are not active.
No codes for the high-pressure fuel pump or the injectors are active.
The fuel rail pressure is above an acceptable level.
The code is logged.
Engine power is derated.
157-0 Engine Injector Metering Rail #1 Pressure: High - most severe (3) No other 157-XX codes are active.
3509-XX codes are not active.
3510-XX codes are not active.
No codes for the high-pressure fuel pump or the injectors are active.
The fuel rail pressure is above an acceptable level.
The code is logged.
The engine may stop.
157-1 Engine Injector Metering Rail #1 Pressure: Low - most severe (3) No other 157-XX codes are active.
3509-XX codes are not active.
3510-XX codes are not active.
No codes for the high-pressure fuel pump or the injectors are active.
The fuel rail pressure is below an acceptable level.
The code is logged.
Engine power may stop.
6323-7 Engine Fuel Supply Pump : Not Responding Properly No 157-XX codes are active.
3509-XX codes are not active.
3510-XX codes are not active.
The actual fuel rail pressure exceeds the desired pressure.
The code is logged.
Engine power is derated.
6323-14 Engine Fuel Supply Pump : Special Instruction No 157-XX codes are active.
3509-XX codes are not active.
3510-XX codes are not active.
The actual fuel rail pressure exceeds the permissible range.
The code is logged.
Engine power is derated. Probable Causes
Diagnostic codes
Electrical connectors
Fuel filters
Fuel rail pressure sensor
High-pressure fuel pump
Fuel pump calibrationRecommended Actions
Contact with high pressure fuel may cause fluid penetration and burn hazards. High pressure fuel spray may cause a fire hazard. Failure to follow these inspection, maintenance and service instructions may cause personal injury or death.
Table 2
Troubleshooting Test Steps Values Results
1. Diagnostic Codes
A. Connect the electronic service tool to the diagnostic connector. Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Download the Product Status Report before troubleshooting or clearing any diagnostic codes.
Note: The downloaded information will be required by the DSN if troubleshooting assistance is needed.
C. Determine if a diagnostic is active or recently logged.
Diagnostic codes
Result: A code in Table 1 is present.
Proceed to Test Step 2.
Result: A code other than the codes in Table 1 is present.
Repair: Troubleshoot the code. Refer to the applicable troubleshooting procedure.
2. Electrical Connectors
A. Check for the correct installation of the ECM J1/P1 and the J2/P2 connectors. Check for correct installation of the connector on the fuel rail pressure sensor.
Connectors
Result: There are suspect connectors.
Repair: Use the electronic service tool to perform the "Wiggle Test".
Repair or replace connectors that are suspect.
Result: There are no suspect connectors.
Proceed to Test Step 3.
3. Fuel Filters
A. Replace the in-line fuel filter that is upstream of the electric fuel lift pump. Refer to the Operation and Maintenance Manual for further information.
B. Replace the fuel filter. Refer to the Operation and Maintenance Manual