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Komatsu PC400LC-7EO Fault code.

Vetech63 · 2019-11-04 07:45

S# A83597 I am getting an irrational fault code of E15 that seems to have no regularity to it. It may go off several times a day, or not at all, which has been making this cumbersome to say the least. When the code does come up, the engine derates and the operator kills the machine which evidently is resetting the computer. I got there Friday to check it out and the code did come up for me, a flashing E15 with a flashing exclamation point. The problem I had was when I tried to narrow down the actual fault code itself, I would push the exclamation point button the code would clear from the screen...…...so I haven't figured out how to get there. So this is where you Komatsu experts can shine for me. Through some research I have figured out that the E15 is engine sensor related, but I need the CA number to narrow this down. Tell me what I am doing wrong and how do I get to what I want to see? I have included a pic of the panel for reference.

Replies14
  1. #1John C.2019-11-04 10:46

    You have to get to the service menu in order to see what the actual fault is. Press the button with the number 4 on it and hold it down. Now press the numbers 1, then 2, then 3 while holding the 4. Wait for a fraction of a second after pressing and releasing the 3 and then release the 4. The monitor should go into service mode. You will see a menu that you can select through by using the triangle arrow buttons on the right side of the key pad. Press the check mark to select a menu on the screen. It is pretty intuitive after that. As I recall there are electrical faults and mechanical faults. It will display fault codes and I don't know if this system will tell you what the codes actually are. You might need a book to read them. Let me know as I might have access to a different model but still a Dash 7 machine.

  2. #2Vetech632019-11-04 18:07

    Thanks John! I tried the hold 4 and hit 1,2, and 3 to no avail. After playing with this monitor, I used the UP arrow with the 1,2, and 3 and was successful in getting to the service menu. The current codes are there but I don't see an active or inactive identifier. The codes I did see are the following: CA553 CA559 CA2249 From what I gather they are all fuel rail pressure codes. Since the machine has not been consistent with this failure I believe it may just be the sensor itself. I will have a new sensor in the morning and will install it. I will report back with the results.

  3. #3John C.2019-11-04 19:23

    I apologize for that. I'm currently working with a Dash 8 system and I read through your post too quick and missed the Dash 7 in the title. I hope I didn't hold you up for much time and I'm glad you figured out about the up arrow You can clear the codes by pressing the same buttons in the same order you did to get into the service menu. Words will come up on the screen that direct you on what to do to clear the codes. By the way, I don't see those codes in any of my materials for the Dash 7 machines. Which engine does this machine have installed? Cummins clone or original Komatsu engine? Hopefully those codes will clear using the machine electronics.

  4. #4LACHAU2019-11-04 23:26

    It seem something wrong! Rail pressure sometime low....sometime high??!! Failure Code CA2249 follow Action Code E11, it's not E15. It's also KOMATSU engine SAA6D125E-5, sir. KOMATSU machine is very complicated!! PC400LC-7 serial No. from 50001 and up do not have those fault codes. But machine has serial No. from 60001 and up has those fault codes!!!

  5. #5LACHAU2019-11-04 23:53

    You can go to SERVICE MENU for several functions check; especially "MONITORING" to check a lot of real time operation of machine.

  6. #6John C.2019-11-05 00:55

    It's nice to find someone else that speaks Komatsu so well. Thanks for the input

  7. #7LACHAU2019-11-05 06:54

    Thank John, it's my pleasure.

  8. #8Vetech632019-11-08 08:54

    Well, it ended up taking a bit more time to get to this due to weather and scheduling. The results below are with new fuel filters to eliminate any restrictions that could have been present at the time of tests. With old common rail sensor; Cold engine temp......idle (1000 rpm as measured on the monitor) Rail pressure 561 KG/CM2 (7979 psi) high idle (1890 rpm) Rail pressure 1120 KM/CM2 (15930 psi) With new pressure sensor Warm engine (135F) low idle (1000 rpm) Rail pressure 422 (6002 psi) High idle (1890) Rail pressure 920 (13085 psi) Operating temp 182) Low idle (1000) Rail pressure 565 (8036 psi) High idle (1890) Rail pressure 920 (13085 psi) As I stated, all of these measurements were from the monitor itself. So to my questions...…….. 1. What is the high idle supposed to be on this engine as I have no specs? 2. What are the parameters for the rail pressure on this engine and at what temp and rpm? Since I have no parameters I don't have all the info I need to diagnose any further. After I changed the sensor and ran the machine at operating temp for about 15 minutes, the E15 CA559 code came back up (after I cleared all previous codes). The engine sounds like it has a slight flutter at the very top of the rpm range but doesn't seem consistent at this point. The machine may run hours and not have the code pop up, or it may do it 5 times in 30 minutes. It is making it dam difficult to narrow down. What would you guys think on this so far? Any ideas? Maybe I should check the low side stuff for debris which I haven't done yet.

  9. #9John C.2019-11-08 09:14

    There is a screen in the banjo bolt at the supply side inlet of the fuel pump. I'm guessing that your rail pressure is low but I don't have any specs to dispute that with. I seem to recall the high side of the rail pressure being in the 20K to 30K range. I also don't remember much of a pressure drop between low and high idle. I am guessing that the RPM readings are probably in spec. Have you checked RPM when the engine is under a load?

  10. #10LACHAU2019-11-09 02:28

    Here you are. Note: 120 MPa ~ 1224 kgf/cm² ~ 17,405 psi.

  11. #11John C.2019-11-09 11:49

    So the question remains, is the observed rail pressure low enough to cause the recorded faults.

  12. #12Vetech632019-11-10 09:07

    X2. At least I know I'm good on the engine RPM.

  13. #13Akliving2020-07-31 15:26

    Did you figure out what the problem was. J have the exact same thing happening with a machine

  14. #14DMiller2020-07-31 15:39

    Caution boys throwing sensors at these. Wiring takes a beating on cranes, a loose cable clamp and a hard or even a soft short to ground or cross circuit could be sending down a primrose path.