CYLINDER AS 3G8194 - Caterpillar

Event E398Conditions Which Generate This Code:The Electronic Control Module (ECM) detects a fault with low fuel rail pressure. The ECM detects the following faults:
The ECM determines that the expected fuel rail pressure is lower than the pressure that is requested by the electronic control system.
Diagnostic code 0262-03 5 Volt Sensor DC Power Supply voltage above normal is not active.
Diagnostic code 0262-04 5 Volt Sensor DC Power Supply voltage below normal is not active.
Diagnostic code 1797-03 Fuel Rail Pressure Sensor voltage above normal is not active.
Diagnostic code 1797-04 Fuel Rail Pressure Sensor voltage below normal is not active.
No diagnostic codes are active for the fuel rail pump.
No diagnostic codes are active for the fuel injectors.System Response:The event code will be logged.The warning light on the control panel will flash.Possible Performance Effect:E398-1The engine will be derated until the keyswitch is turned to OFF.Troubleshooting:Test Step 1. Low fuel pressure may be caused by the following faults. There can be a fault with the fuel return system. There can be a fault with the fuel pressure control. There can be a leak in the high pressure fuel system.A failed relief valve, the fuel pump or an electronic unit injector may cause an event code to be logged.The event code does not represent a fault with the electronic system. This event indicates low fuel rail pressure. Refer to Systems Operation, Testing and Adjusting, "Fuel System - Inspect".Results:
OK - STOP