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Ford LRG-425 efi diagnostics

NJSchrader ยท 2022-12-01 21:57

I'm helping a neighbor with his recently acquired JLG 450aj boom lift. It is a 2001 model with the ford LRG-425 efi engine. When key is turned to run, the electronic throttle body will cycle open/ shut rapidly, and when started the engine will run rough at a high idle and then shut off after 20 seconds or so. The engine at some point has been updated from it's original ECM to the new style EPM with Bosch throttle body and O2 sensor, etc. The wiring harness has been checked over thoroughly. Temp, MAP, crank and cam position sensors, as well as throttle position sensor in the throttle body check out. We are leaning towards a fault in the EPM itself. When attempting to pull fault codes, we get 123, meaning no codes present We would like to plug a laptop onto the diag connector, but have not been able to aquire the FPP Display software. I've read previous threads regarding this engine in other equipment, and would appreciate any insight. A side note, the engine will start and idle perfectly when the installed throttle body is disconnected, and engine harness plugged into the spare TB.

Replies12
  1. #1Birken Vogt2022-12-01 22:43

    https://www.editechinfo.com/file-share for FPP display I can probably help you with the software and troubleshooting if you can get this going.

  2. #2excavator2022-12-02 12:53

    Man, I wish I had known you when I was fighting a 425 EFI in a JLG. This would have been a lifesaver.

  3. #3Birken Vogt2022-12-02 13:11

    I only work on generators (at the moment), don't know EFI systems specifically, but I am a pretty good fighter of computers and have managed to interface the software to most everything I put my mind to except one, still working on it but it is not important. Most of these spark ignition computer systems use the same or similar software.

  4. #4excavator2022-12-02 13:35

    I fought one for a long while, crank no start. I bought the diagnostic cable ect but was unable to find any info as far as installation on a PC. Your info looks like what I needed, don't need it anymore but might just try it to see if I can make it work. Thanks.

  5. #5Birken Vogt2022-12-02 13:49

    If you need any help just ask, if I come to any engine with this control system I attempt to connect to it now so I learn the software and can have it work for me when I really need it.

  6. #6NJSchrader2022-12-02 16:17

    Thanks for the download link. I had a chance to look through the instruction pdf, and have a grasp on how it works. What did you use as a dongle to connect to the machine? I'm assuming it communicates over CAN bus. I see there is the ECOM CANCapture device, but was thinking any USB to CAN device 'should' work, with the CAN high and CAN low connected appropriately.

  7. #7Birken Vogt2022-12-03 01:05

    This device https://www.cancapture.com/ecom It does both CANBUS and RS232 to the Econtrols software. The software rapidly cycles through the possible ports looking for something to connect to. I had one apart once and it does look pretty proprietary but it is not too expensive.

  8. #8NJSchrader2023-01-24 22:44

    This is an update to our progress with the JLG 450AJ boom lift and Ford LRG-425. We acquired an ECOM usb cable and appropriate 4-pin adapter harness to connect to the diag connector. While running, we had DTC's 311, 313, 315, and 321 as active faults. All being "Injector open or short to ground" for a given cylinder. We also had DTC 412, which is "spark coil 1 primary shorted". After following the flowcharts for each DTC, and not finding any faults in wiring, injectors, or the coil assembly, we have determined our problem lies in the EPM itself. Is anyone aware of a reputable shop that is able to work on and repair these E-controls EPM's? Thanks

  9. #9Birken Vogt2023-01-25 00:45

    erdltdinc.com was suggested to me as somebody who could repair these. Confirm you really do have those injectors and coil present in your application? I have several units that log a continuous fault code when running of starter solenoid ckt open/gas valve ckt open because they are simply not connected, they are controlled another way.

  10. #10Jeff Day2024-08-08 14:56

    I to am struggling with the exact system this thread started with. Been converted and all. ERD is local to me and they checked the ecm and throttle body. It all checked out. Mine floods when you try and start it. Only way you an make it run is start it on propane and trick it into running on gasoline. It runs great after intial start. Sometimes you can get it to start on gasoline if you force the throttle body to WOT. I have swapped every sensor and checked every wire. ERD told me that the connectors on the ecm are fragile and the contacts fail regularly. Check those. Mine are fine.

  11. #11Jeff Day2024-08-08 14:59

    Also You can hold the pushbutton on the side of the ground control box and the check engine light will flash all the codes generated the last time it run. JLG offers all the manuals online to decode the flashes.

  12. #12zibby2025-09-26 20:15

    I gave Genie z45 with same engine. Do you have any updates on your issue? Did you get it resolved?