Machine I'm looking at is a 2005 model. LGP if that helps. I haven't gotten the serial number out of the salesman yet. Engine is a 3126B. When I looked at the machine, the service codes indicator was lit in the dash. They weren't active codes, because if you shut it off and restarted, it would stay off for a few minutes, and then return. I'm still trying to get the exact codes, but primary information is there were 3. Fuel pressure, actuator pressure, and throttle position sensor. The service advisor claimed, in his opinion, that the pressure codes were generated by partially gelled fuel. When I asked how gelled fuel would be related to the HEUI system, he then did quickly mention that there could maybe be a leaky injector, but doubted it. Engine has about 3500 hours, it was a complete Caterpillar "crate engine" according to the previous owner. I am hoping to get some more info today, these dealer guys are really starting to **** me off.
Need a S/No and exact Codes to start looking. There are 20+ different prefixes of D6N. A suggestion. If the SERV CODE icon is not lit on first startup that means there are no Active Codes at that time. As soon as it lights up scroll through the Codes on the Monitor Panel to see which of them has lit up the SERV CODE. That will give a much better idea of what's going awry.
What is the process to view the codes?
Depends on the Monitor Panel but generally if you press the test switch (circled) the display can be scrolled in a loop sequence from the hourmeter to distance travelled, tacho function, Diagnostic Codes, auto-kickdown mode, park brk status, & gear selection. The display on your tractor may not have all these functions but it will certainly have the Codes. Keep pressing the switch and eventually it will return back to the hourmeter.
BTW whichever Code or Codes are Active when you scroll through them the SERV CODE icon will light up. For all the Logged Codes it will stay out. Check out Posts 50-52 of this thread if you want to clear all the Logged Codes before startup with nothing more than a couple of pieces of automotive wire. It might pay you to clear everything if there are no Active Codes and then simply see which ones come back after running the machine for a few minutes. HeavyEquipmentForums
When you press the button and get to the code section of the menus, the codes will automatically cycle through, most times a lot faster than you can write them down. The mode will keep cycling until you change it be pressing the button again. If you don't get the full code on the first cycle, you will be able to get more when it comes back around again.
I've found that a smart phone set to video mode works a treat in getting the full list without getting dizzy watching the display go round in circles.. Also worth mentioning that each Code will be presented in 2 stages. The first is the ECM that registered it, 030, 036, 081 or similar. The second is the Code itself, 248 08, 096 03, etc. To get troubleshooting info really needs both sets of numbers.