J1939 CAN bus data

4x4dually

4x4dually

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Does anyone know if the J1939 CAN bus data is available at the ODB port under the dash? Does anyone know how to get it there if it is not already available?

I'll figure it out, but wanted to see if anyone has already tackled it first.
 
if not, I do know it can be read off the three pin data port on the engine.

what are you up to?
 
Oh hell. Just a little sumpin'. I really don't want to spill the beans quit yet until I make sure it will work. I have found a readout that will display four different engine parameters just like my attitude (which would give me eight at once) as well as flash engine trouble codes when they occur with text description so I know what they are as soon as the light goes on. Then I can make the decision whether to stop the truck or keep going down the road. It is pretty sweet. I'm surprised someone hasn't already got one on a truck....maybe someone does. They are affordable and look great. Not built for the automotive market but a whole lot better. Any guesses???? :D

Edit: It will also take the engine CAN data and drive up to like 8 other gauges! A racers dream!
 
is it not the one on the drivers side of the motor closer to the bottom where your typical edge comp would plug into?
 
That is what I DIDN'T want to hear there cowboy!!!! If that is the only one, I will have to split it and impedence match the stub so my Edge and my "mystery device" can both read the data.

I also heard that cummins (or maybe even the flunkies at Dodge) can "turn on" the data being sent to the diag port under the dash. I still need to research that part of the equation.
 
4x4dually said:
Does anyone know if the J1939 CAN bus data is available at the ODB port under the dash? Does anyone know how to get it there if it is not already available?

I'll figure it out, but wanted to see if anyone has already tackled it first.
Click to expand...

is this the square Cummins marine gauge setup? it wont work on our trucks. allreasy tried it. 1939 is 29bit identifiers, our truck uses 11bit identifiers. both can run on the same bus though.
 
joeservo said:
is this the square Cummins marine gauge setup? it wont work on our trucks. allreasy tried it. 1939 is 29bit identifiers, our truck uses 11bit identifiers. both can run on the same bus though.
Click to expand...

Really? That sucks. I happen to know an individual that works at the plant that makes these so we were going to try to make one work. Who makes the one you are talking about?

What year uses the 11 bit identifiers, all of them, or just the newer ones?
 
Last edited:
More info. I'm waiting to hear back to see if they support 11 bit idents.

What is Standard CAN and Extended CAN?

In Standard CAN the identifier is 11-bits long and in Extended CAN the identifier is 29-bits long. As specified in CAN protocol version 2.0, a CAN controller which complies to V2.0A must have 11-bit identifier. Whilst in V2.0B, it can be either 11-bit or 29-bit. With V2.0B active, a CAN controller may transmit and receive both standard and extended frames. With V2.0B passive, a CAN controller may transmit and receive standard frames, and ignore the extended frame without error.
 
He said their's is configurable and we just need to set it up right and it will work. We'll see in the weeks to come! :D
 
i would love to help to get this working, this display has a lot of cool features. let me get a pic of the display i am talking about and make sure we talking about the same one, or send me a PM of the link of the one you are talking about.
 
Not sure if the 2nd gen is the same, but on a 3rd gen (my engine is an 04) the can bus is at the OBD port. (have the pin #'s at home). I would be interested in trying one of these as well. As I currently don't have a check engine light that is fed from the cummins ECM (since my diesel conversion doesn't use a dodge PCM).

BTW, I put an 04 cummins into my Ford Excursion. My tranny controller also has the capability to read CAN bus data as well. Just haven't spent the time trying it yet...
 
4x4, the one i have is different. no offense, but it is much nicer. has some graphics behind it.

here is a pic from my scanner. you can choose 4, 2 or 1 parameter.
 

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I was told by a feller that you could have a cummins tech or someone of the sort 'turn the CAN data on' and it will be send to the data port. I have yet to research this as I feel like if I call Southern Plain Cummins and ask them they are gonna say..."huh".."a what"..."why"....

I'm not anticipating an 120 ohm impedance cables going to the data port anyway because most of the time it would be an unterminated stub and may cause reflections and bad data but if I could get that turned on I wouldn't have to splice into the bus....which is only two wires and a ground so it really wouldn't be hard either.

I'll definately post up if I get 'er done. Chances are joeservo that the module you posted is made for Cummins by Murphy. They make a butt load of cummins parts for them of this nature.
 
i would not worry about the 120ohm load. i have used CAN up to 250k with
1k loads.

i have a friend that works at the dealer, i will see if he can dig into further.
 
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