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J1939 to Cummins...?
I've tried a few times to get a clear answer on this. If I call Cummins, they say go talk to Garmin. if I call Garmin its vice-versa 😮
I have older Garmin 5212s but thinking of upgrading to new Garmin GPSMap 2143s which include a J1939 port to read engine data. The question is what extra equipment is needed to read data from a Cummins QSC engine. Some will say you need a gateway but gateways are more expense so I just want to make sure before I spend the money on it. Just wondering if there's a way to connect the Cummins directly to the J1939 port...?
I think it may be a case of needing to ask very specifically phrased questions of the manufacturers. If I were talking to Garmin I would say something like I see your GPSMap 2143 has a J1939 port on it, from there can I assume that it translates J1959 to NMEA 2000?
If I were talking to Cummings I would ask does your engine output J1939 or do you have custom PGNs for your engines? If they say we use pure unadulterated J1939 then you can probably assume that your Garmin with a J1939 port can use that data without a gateway. Or if they say no we have proprietary PGNs, then you must have a gateway.
J1939 is a standard like NMEA 2000 and if the Cummings engine is outputting J1939 then any J1939 enabled instrument or display should be able to read the data coming out. They are all based on CanBus and NMEA 2000 and J1939 are customized versions of CanBus. They add information to the beginning and end of the string to identify where it is coming from and where it is going and how it should be used so it is like UK English vs US English vs AUS English Vs NZ English. They have their quirks but we are all speaking the same base language.
What year and model of QSC engines do you have? Have you been able to confirm they have J1939 available?
Garmin has equipped their current GPSMap line with J1939 interfaces but make very few cables to go from the Micro-C connector to engine manufacturers connectors. There are myriad different connectors for various engines and I get the feeling the MFD manufacturers aren't super interested in getting into the adapter cable business. So, if you can figure out how to get the data to the MFD, the MFD can convert it.
There are specialists like Maretron and Yacht Devices that make engine gateways and quite a few adapter cables. I own Yacht Devices U.S. so I'm most familiar with their products.
Thx for comments. It is a 2010-era Cummins QSC 8.3. Yes we already have the old Smartcraft display up at the helm which presumably is reading CANbus data. so its not a matter of engine to NMEA2000, its more a matter of inserting the CANbus data from the smartcraft into the J1939. Garmin says CAN is a portion of their J1939 so Ben could be right in the idea that a complex harness is involved.
From what I read, I'm likely stuck buying a purpose-built gateway in order to make this work, like the one Panbo reviewed recently from Mercury "Smartcraft Connect"....
Ben, I have confirmed with a level 2 Cummins Tech that my QSM11's diagnostic port has both J1939 and J1708 in a round 9-pin Deutsch connector. And my Garmin mfd has their J1939 port for engine display. Does anybody make that cable or do I have to create it? Also, I don't know yet if my fuel level sensors are going to be on that diagnostic port. If not, then maybe I need a Yacht Devices sensor for analog resistance measurements to put the tank levels on my N2K backbone?? BTW, the level 2 Cummins guy was super responsive and helpful.
I have two Yacht Devices interfaces, one each for my Cat C12 engines, along with the necessary J1939 Deustch adapter cables. Works nicely. Their website lists an adapter for Cummins also.