STUD 6K2039 - Caterpillar

Use this procedure to troubleshoot a high fuel rail pressure. Also, use this procedure if one the following event codes is active or logged.
Table 1
J1939 Code and Description CDL Code and Description Comment
157-15
Engine Injector Metering Rail #1 Pressure : High - least severe (1) E396 (1)
High Fuel Rail Pressure The fuel rail pressure is above a threshold.
157-16
Engine Injector Metering Rail #1 Pressure : High - moderate severity (2) E396 (2)
High Fuel Rail Pressure The fuel rail pressure regulator has opened due to high rail pressure.
A derate is applied.
Table 2
Associated Codes
J1939 Code CDL Code Troubleshooting Procedure
157-3 1797-3 Troubleshooting, "Sensor Signal (Analog, Active) - Test"
157-4 1797-4 Troubleshooting, "Sensor Signal (Analog, Active) - Test"
1076-7 18-7 Troubleshooting, "Fuel Control - Test"
1440-0 E1106 (3) Troubleshooting, "Fuel Flow is High"
1440-15 E1106 (1) Troubleshooting, "Fuel Flow is High"
1440-16 E1106 (2) Troubleshooting, "Fuel Flow is High" Probable Causes
Codes
SensorRecommended Actions
Table 3
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Look for active codes that are associated with the system for the event code.
Codes
Result: An associated code is present.
Repair: Troubleshoot any associated codes before continuing with this test.
Result: A code is active or logged.
Proceed to Test Step 2.
Illustration 1 g03812117
High-pressure fuel pump
(1) Rail pressure sensor
Table 4
Troubleshooting Test Steps Values Results
2. Verify the Fuel Rail Pressure Sensor Reading
A. Turn the keyswitch to the OFF position.
B. Release the pressure in the high-pressure rail by loosening the end plug on one of the last two fuel accumulators. Refer to Testing and Adjusting, "Fuel Rail Pressure - Release" for instructions on how to release the pressurized fuel.
C. Turn the keyswitch to the ON position.
D. Connect Cat ET.
E. Use Cat ET to monitor the following parameter:
- "Fuel Rail Pressure"
Note: The fuel rail pressure sensor is not reusable. If removed, then the sensor must be replaced.
Sensor
Result: The "Fuel Rail Pressure" is 0 8 MPa (0.0 1160 psi).
Proceed to Test Step 3.
Result: The "Fuel Rail Pressure" is greater than 0 8 MPa (0.0 1160 psi).
Repair: A failed fuel rail pressure sensor has been detected. Perform the following procedure:
1. Release the pressure in the high-pressure rail by loosening the end plug on one of the last two fuel accumulators. Refer to Testing and Adjusting, "Fuel Rail Pressure - Release" for instructions on how to release the pressurized fuel.
2. Verify the "Fuel Rail Pressure" reading in Cat ET is 0 8 MPa (0 1160 psi) prior to servicing the fuel system.
3. Replace the fuel rail pressure sensor.
Proceed to Test Step 3.
3. Check for Codes
A. Start the engine.
B. Run the engine until normal operating temperature has been reached.
C. Bring the engine to high idle.
D. Connect Cat ET.
E. Use Cat ET to monitor the following:
- Codes
Codes
Result: A code is not active.
Return to service.
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).