working on a 966m(serial # kjp) that is having def issues, it currently has a 5856-9 (j1939 data link 3 abnormal update rate) active code and e1389 (SCR operator inducement) event code and is in "limp mode". the def gauge also reads empty, i replaced the def header in the tank and the vlpm (had low output voltage) and PETU harness (corrosion in some of the connectors) and am at a loss which direction to head, ET shows in communication summary device 1: engine #1 aftertreatment controller is unable to communicate with device #2 aftertreatment def controller, there are no obvious broken data wires and all resistors measure 120 OHMs. any help would be greatly appreciated, thanks.
Is this machine close to 10k hours? My 966m (if I remember correctly ) threw that code and I had to have the system cleaned and reset by the dealer. I think that code automatically trips every 10k hours.
just over 10700 hours, what has to be reset?
They hook up Cat ET and reset computors. I wasn't there when the tech worked on it, but they took the dpf off, sent it away and then check other things as well. Sorry I can't help you any farther. I know it was down for 3 days during the process as I live out in the sticks.
If the machine is in "limp mode" then AFAIK even if the Diagnostic Code is cleared by replacing parts, etc, it will still require the system to be reset using Cat ET by a tech of some sort, be that dealer or independent. I am not certain whether or not the reset requires factory passwords in which case it would be a dealer-only job. What's the suffix in your E1389 Event. -1, 2, or 3.? I'm guessing 3. Datalink Test is what you should be doing for the 5856-9 Code. This Code inhibits the operation of the exhaust aftertreatment system.
thank you, correct guess on severity 3. no factory password needed for dcu reset but could not reset do to conditions not met. hooked oscilloscope to can bus wires and wave forms were erratic from dcu to aftertreatment ecm , removed dcu and installed it in another 966m out in the field and threw same 5856-9 code and et shows same unable to communicate between aftertreatment ecm and dcu. dcu is on backorder with no estimated ship date.
Don't you just love it when that happens.? Thanks for the info that no factory passwordis are needed for the reset. That's filed away for future reference.
yes and just about everything else emissions related requires factory passwords. I need to learn a bit more about the can bus/data link systems on cats, i dont come across alot of those issues in my day to day.
The reason I thought it might requir passwords is that on many other models that have been dealt with on HEF recently regarding getting the machine out of limp mode following an aftertreatment system lockout issue I can't remember a single one that DIDN'T require one..............
luckily for me 5856-9 is self clearing on startup if conditions are met