Cat c12 trim code locations

Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by Smokinbacon79, Mar 19, 2019.

  1. Smokinbacon79

    Smokinbacon79 Bobtail Member

    10
    0
    Mar 19, 2019
    0
    The last guys to work on my truck replaced the ecm thinking it was the problem. Turns out it was actually the fuel pump. I put a new pump in and bled the system and now it sounds like only one injector is firing while cranking. Could this be due to incorrect trim codes? All of them are set to 2300 as the default. I read somewhere that the trim codes are put on the injectors from the factory. If this is the case where exactly are they?
    Thanks in advance
     
  2. Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.

  3. Smokinbacon79

    Smokinbacon79 Bobtail Member

    10
    0
    Mar 19, 2019
    0
    Also should be worth noting that all the solenoids work. Tested with cat et
     
  4. spsauerland

    spsauerland Road Train Member

    4,296
    10,886
    May 31, 2010
    West Harrison, In
    0
    Trim codes will not cause a no start condition. Trim codes are 4 digits on the solenoid body, all numbers on a C-12.
     
    SAR Thanks this.
  5. Smokinbacon79

    Smokinbacon79 Bobtail Member

    10
    0
    Mar 19, 2019
    0
    Fixed the trim codes. As you said still no start. Sounds like it's trying a little harder to start. I can connect to it using the diagnostic connector with cat et, and it doesnt throw any codes besides low coolant. I tried to use on board diagnostics to pull engine codes just for ####s and giggles and it said the ecm wasnt present. (MTVR, I'm a mech in the Marine Corps) however it still can pull up a hardware and software ID, just not when I try to pull codes for some reason. Also noteworthy that I haven't noticed on other engines is that I can prime it with the hand pump enough to where it send fuel through the pressure regulator into the return line.
     
  6. spsauerland

    spsauerland Road Train Member

    4,296
    10,886
    May 31, 2010
    West Harrison, In
    0
    Does your tach show about 200 RPM when cranking and what is your fuel pressure when cranking?
     
    SAR Thanks this.
  7. spsauerland

    spsauerland Road Train Member

    4,296
    10,886
    May 31, 2010
    West Harrison, In
    0
    Thanks for your service. I remember seeing the MTVR in Iraq in 2003 (Army wheeled vehicle mechanic) and being jealous of the those. C-12 and fully independent suspension... Cadillacs!
     
    SAR Thanks this.
  8. Smokinbacon79

    Smokinbacon79 Bobtail Member

    10
    0
    Mar 19, 2019
    0
    She cranks at around 200 to 250 until it tries to start and then it goes up to around 350 while its cranking. Itll idle terribly for about 3 seconds and then die
     
  9. Smokinbacon79

    Smokinbacon79 Bobtail Member

    10
    0
    Mar 19, 2019
    0
    And honestly for the amount of abuse the operators put on these trucks they handle it great
     
  10. spsauerland

    spsauerland Road Train Member

    4,296
    10,886
    May 31, 2010
    West Harrison, In
    0
    Is the original ECM back on it? Just curious about timing calibration on replacement ECM. Also, what lead to fuel transfer pump failing. Does the fuel look contaminated? Try running from Jerry can to see if issue with fuel lines or tank? Someone didn't manage to put Mogas in it?
     
    SAR and AModelCat Thank this.
  11. spsauerland

    spsauerland Road Train Member

    4,296
    10,886
    May 31, 2010
    West Harrison, In
    0
    Also, have you checked fuel pressure regulator in fuel filter base. Might be easy to swap from good running unit. Looks like hex plug with I think 1 1/16" socket fits.
     
    SAR Thanks this.
  • Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.