P023F Troubleshooting

[ltdriser]

Hey guys just looking for a little trouble shooting advice.  Was driving to work today and the engine died mid drive.  I couldnt get it started and now it sits in front of the house.  I'm a do it yourselfer so I couldnt just blindly take the truck to some auto shop without first investigating.  The one and only code I have on the MIL is P023F - Fuel Pump Secondary Circuit open.  Have you guys seen/dealt with this code by itself? Truck is a 2015 1500 LTZ 5.3L. I checked the Fuel Pump fuse and relay quickly before I took the other car to work, both seemed fine.  Any direction on troubleshooting when I get home would be greatly appreciated.

I plan tonight to take a look at the FPCM fuse (pray thats all it is), check the connections for corrosion on the FPCM then unplugging and replugging a few times.  Aside from that and grabbing the voltmeter do you guys have any troubleshooting tips or experience with this trouble code.  I'm trying to avoid taking a shot in the dark.

[Eddie 70]

 

[jay webb]

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the G12 Fuel Pump. Connect a test lamp between battery positive voltage and the G12 Fuel Pump harness connector terminal 2. It may take up to 2 min for all vehicle systems to power down.
2. Verify the test lamp illuminates.
   • If the test lamp does not illuminate
   1. Ignition OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module.
   2. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, refer to Component Testing in this diagnostic.
   • If the test lamp illuminates
3. Ignition ON, connect a test lamp between the supply voltage circuit terminal 1 and the low reference circuit terminal 2.
4. Verify the test lamp turns ON and OFF when commanding the Fuel Pump Enable On and Off with a scan tool.
   • If the test lamp is always OFF
   1. Ignition OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module.
   2. Test for infinite resistance between the supply voltage circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
   3. Test for less than 2 Ω in the supply voltage circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, test or replace the K111 Fuel Pump Driver Control Module.
   • If the test lamp is always ON
   1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K111 Fuel Pump Driver Control Module, ignition ON.
   2. Test for less than 1 V between the supply voltage circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, test or replace the K111 Fuel Pump Driver Control Module.
   • If the test lamp turns ON and OFF
5. Test or replace the G12 Fuel Pump.

1. Ignition OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module.
2. Connect a DMM, set on diode setting, with the positive lead at terminal 16 and the negative lead at terminal 9 of the K111 Fuel Pump Driver Control Module.
3. Verify the DMM displays between 0.4–0.8 V.
   • If not between 0.4–0.8 V

     Replace the K111 Fuel Pump Driver Control Module.

   • If between 0.4–0.8 V
4. Connect a DMM, set on diode setting, with the positive lead at terminal 9 and the negative lead at terminal 16 of the K111 Fuel Pump Driver Control Module.
5. Verify the DMM displays OL.
   • If not OL

     Replace the K111 Fuel Pump Driver Control Module.

   • If OL
6. All OK.