Engine Monitoring J1708 and J1939? - Printable Version

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+--- Thread: Engine Monitoring J1708 and J1939? (/showthread.php?tid=6098)

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Engine Monitoring J1708 and J1939? - Wanderman - 06-10-2021

Hi All,

  So my 1996 Series 60 would be DDEC III and has the HD4060 trans.I believe.

So the question is... is that ONLY J1708 or is J1939 data piggy backed on it with two more pins? I won't be at the coach for a few weeks, but am putting together a monitoring package that would work and give me maximum data (PIDS)

Likely I will hard wire the box, but may just bet a molex connector and wire that instead so i can remove if needed/wanted.

Has anyone tried the Bluefire version rather than the VMSPC? I like the idea of having it also displayable with an Anrdroid tablet since I have a few lying around and Bluetooth option is nice to have so you could potentially bring the tablet back by the engine while working on it.

With bluefire i have to figure out which one to buy AND figure out what adapter to get (from another company, no less!)

Opinions?

Thanks!

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RE: Engine Monitoring J1708 and J1939? - MrE - 06-10-2021

Rick, you have J1939 with your coach. You'll want the 9-Pin J1939/J1708 Green Bluetooth Apple/Android/Windows Adapter. You can read my recommendation on this link http://newellgurus.com/showthread. J1939 is pretty straightforward, you have a + and a - along with a CAN high and CAN low. Wire in a J1939 receptacle to your current diagnostic port.

BlueFire for Motorhomes is exactly what I'm planning on using when I pick up my coach in Missouri. I had the DD 8V92 and Allison HT740 powertrain replace with a Cummins ISM a ZF transmission. I plan on monitoring it very closely on my trip.

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RE: Engine Monitoring J1708 and J1939? - Wanderman - 06-11-2021

Jon,
  Hmmmm I cannot look at the connector in the coach , but I did find a schematic on the forum. J1939 has two additional connections CAN + and - but that is not reflected in the pinout. Would you know which pins on the connector they are?

I am having a custom cable made up that will go from the current Bluefire 9 PIN Deutsch directly to our 12 PIN MOLEX.

Thanks!

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RE: Engine Monitoring J1708 and J1939? - MrE - 06-11-2021

Rick, you should be able to purchase the adapter cable already made up. SilverLeaf used to sell them, but there are plenty of suppliers that sell diagnostic adapter cables. The problem when searching is verbiage, I've seen your 12-pin Molex also referred to as GM ODBI. A lot of our forum members are using the VMSpec from SilverLeaf, they can chime in on how they hooked theirs up.

This image should help;

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RE: Engine Monitoring J1708 and J1939? - Wanderman - 06-11-2021

The only question that remains is the two CAN additional wires for J1939. WHich pins on the 12 PIN MOLEX do they correspond to? And in the second photo from the forum, there seems to be a 7th pin??

I have a company making up the cables for the Bluefire monitor that will be 9 PIN J1708/J1939 directly to our 12 PIN MOLEX. Then it will be turn key and work with Windows/Android/Apple

       

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RE: Engine Monitoring J1708 and J1939? - MrE - 06-11-2021

Rick, you're making this too complicated. Only 4 wires are needed for a CANbus interface. Actually, a more common interface is OBDII. My Cummins Inline 5, factory Cummins diagnostic tool, comes with adapters for 3 common truck interfaces to OBDII.

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RE: Engine Monitoring J1708 and J1939? - Wanderman - 06-11-2021

Jon,
No, I am not. There is additional Data available on the 2 extra CAN lines above and beyond the J1708. I'd like access to everything I can get. If it's a simple matter of adding to more wires to my adapter...it's an easy fix.

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RE: Engine Monitoring J1708 and J1939? - Wanderman - 06-11-2021

This document has a bunch of useful stuff including PID on each bus for DDEC

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RE: Engine Monitoring J1708 and J1939? - MrE - 06-11-2021

Rick, what you have to realize is that J1708 is a predecessor to J1939. Slower interface and not as robust. There is nothing on the J1708 interface that is not on the J1939 interface.

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