I have been having some fuel related problems starting a few weeks ago. I would be working and the machine would loose power and want to die. I replaced all 3 of the fuel filters and thought it was fixed but after a few hours of working it it did it again and then set off two codes. E396 High Fuel Rail Pressure (2) 1797-4 Fuel Rail Pressure Sensor voltage below normal The service repair manual that I have says that E396 indicates High Fuel Pressure and could be one of 3 things: 1. a failed relief valve 2. the fuel pump 3. an electronic unit injector It then refers me to Fuel System Inspect section which tells me to check the fuel cap breather and everything related to low fuel pressure. I have checked these things and nothing has corrected the problem. My question is since it is starving for fuel, why is the high pressure warning coming on? What would you guys try next? I feel like its probably the fuel pump but I don't want to go throwing parts on it hoping it fixes my problems. Could it be a faulty fuel rail sensor causing the problem? Thanks for any and all help. Danny
I would go after the fuel rail pressure sensor fault first. If the sensor is not correctly registering the pressure then all sorts of other events including the E396 could stem from that. 1797-4 Fuel Rail Pressure Sensor : Voltage Below Normal Troubleshooting - "Sensor Signal (Analog, Active) - Test (Sensors on the J2 connector)" Procedure attached. If you want a complete electrical schematic please quote the machine Serial Number.
Nige- thank you for the information. I went and unplugged the sensor checked for moisture or corrosion and plugged back in and it appears to be working properly now. The codes and logged but no longer active.