Adding J1939 to a 3 box for allison swap

[cadillackid]

OK so I decided to start a new thread for this... this will be a multi-part post put up in small sections so be patient.



I wanted to test out the AU electronics J1708 to J1939 converter that was brought up in another thread..


swapping an allison 1000,2000, or 3000 into an early navistar 'E' series engine (T444E, DT466e) pre 1998 can be tricky as the older 3-box computers have no J1939 datalink to connect to the 3rd gen transmissions..


installing a manual throttle box wit ha physical throttle link could work, however is difficult in and of itself..



there was some confusion about using this adapter in the other thread so I figured id try and help out here...


I obtained the device and all the available cables for it.. including the 9 pin to the Deutsch connectors, as well as the 9 pin to an open harness.. yes I couldve easily made my own, but the pre-made stuff is nice and easy to use.. and probably the best solution for someone just starting out.


I also ordered the suggested USB to Serial device to use for diagnostics (really any Serial port will work.. either a hard port on an older laptop or if you already have your own USB to Serial (RS232) cable ready to go..


the USB cable is NOT simply an adapter that converts a USB A into a 9 pin male.. it is an actual functional device with electronics...



Once installed in windows it will show up in device manager under com ports and have a com port number.


AU electronics suggests teraterm but you can use any other serial terminal software you would like.. such as PuTTY or Procomm-plus.. or if you are on a MAC you can use ZOC or decisive tactics..





diwnload teraterm from their github.. the zip file appears to be incomplete.. so if on windows download the exe and install it.. it goes easily.


open teraterm and then select serial and your USB com port..



next you want to open settings and then 'serialport' and change the baud rate to 115200





-Christopher

 

[cadillackid]

for this first test I want to find out if I can even read the J1708 from the school bus datalink... (mine is a single box but the 6 pin diagnostic connector on yours will look the same.


we will use the red and black wires (power / ground).. and the purple / brown (J1708 lines).. leave the green / yellow alone for now..



I have the pins that fit the connector so I put some on for easier testing..





next I went and poked the pins into my J1708 dashboard connector... you have to use the plus and minus power provided by the J1708 connector to power your AU device.. this is the red wire.. the black wire goes to the ground pin on the dash connector.


your A and B pins are your J1708 wires from your AU device...



here is a standard pinout for ther 6 pin connector.. if you have a somewhat newer IH, one of the other pins is the datalink to your ABS controller..








be careful poking the power wires in as they are hot All the time even with the key off..

 

[cadillackid]

now that we have everything wired up, turn on the key and see what happens.. you should see data start to scroll across your screen.. you should see something get read from your J1708.. (ignore the errors for J1939 since its not connected anywhere yet.)..





notice I have 0 road speed.. it shows an MID 164 (which is HPOP pressure but the device doesnt support it..).. and also shows Odometer and engine run hours..


so its talking to the J1708 side.. I tried noving my throttle but I didnt have the engine on so TPS may not have been transmitted... I ran out of daylight for today so that will be in my next tests..



-Christopher

 

[nikitis]

Great info.

Questions. I'm sure you are getting to this part, but how does it all connect once the new transmission is being used? So I get that you are using that open harness into the J1708 port, I get that, and that into the AU device. Then you are using the USB to DB9 cable to go into the laptop.

So when not using the laptop, and you want to connect your transmission up, do you unplug the DB9 to USB cable that would normally go to the computer, and connect your transmission up to that same DB9 port?

Does it go 3000 transmission -> TCM -> AU device -> J1708 Port?

That's where i'm confused at. What is the chain of connections when in actual use with a modern transmission? I'm sure you are getting to that part. The suspense is killing me.

Also good explanation with the color matching wires.

I had a thought that if it does require use of the J1708 port when done. I want to use that port for other things like a digital dash. Since we know it's a token ring network essentially because that's how CAN works. I could potentially solder the open harness in to those 4 wires behind the J1708 Connector. A, B, Power,GND, leaving my actual grey connector available for a bluefire, assuming I can keep the noise down with a twisted pair as the documents require.

 

[cadillackid]

Great info.

Questions. I'm sure you are getting to this part, but how does it all connect once the new transmission is being used? So I get that you are using that open harness into the J1708 port, I get that, and that into the AU device. Then you are using the USB to DB9 cable to go into the laptop.

So when not using the laptop, and you want to connect your transmission up, do you unplug the DB9 to USB cable that would normally go to the computer, and connect your transmission up to that same DB9 port?

Does it go 3000 transmission -> TCM -> AU device -> J1708 Port?

That's where i'm confused at. What is the chain of connections when in actual use with a modern transmission? I'm sure you are getting to that part. The suspense is killing me.

Also good explanation with the color matching wires.

I had a thought that if it does require use of the J1708 port when done. I want to use that port for other things like a digital dash. Since we know it's a token ring network essentially because that's how CAN works. I could potentially solder the open harness in to those 4 wires behind the J1708 Connector. A, B, Power,GND, leaving my actual grey connector available for a bluefire, assuming I can keep the noise down with a twisted pair as the documents require.

so the yellow green wires on the same DB9 that the other 4 wires come off of will go to your allison... your allison harness "should" have the yellow / green wires in it for the link.. if they are different colors, i have the pinouts depending on what type and generatiom of transmission you end up with.
the DB9 on the AU that goes to the laptop will be empty unless you want a laptop on it for monitoring, its not integral to the device functioning..



most likely you will wantto put the red and black wires on a power / ground that is Ignition power controlled.. otherwise you AU will stay powered even when the engine is off and create a parasitic load on your batteries..


the other 2 wires.. purple / brown you cna do exactly as you describe.. 'T' the into the existing wires behind the dash leaving your 6 pin port open for a bluefire or a servicemaxx tool, etc... its built the way you thik it is.. a data BUS so multiple devices can share those 2 wires..


the J1939 is also built in this manner so multiple devices could be on it.. ie you could install a9 pin connector parallel into the yellow / green wires and use a Nexiq device and allison DOC if you wished..

 

[nikitis]

Made a simple wiring diagram describing what you said. Check for errors if you would:

 

[cadillackid]

Made a simple wiring diagram describing what you said. Check for errors if you would:

this is it!! except for ignition power youd have Bat+ going into the switch and then switched coming out... otherwise you got it.


and this is good for allison 1000/2000/3000 WTEC-III, as well as 4th gen, and non SEM 5th gen.



for the 3000 series you'll have an additional tap into the yellow / green wires for your digital shifter pad... the 1000/2000 wont have that additonal tap into the yellow / green, they use mechanical shifters

 

[nikitis]

Updated. Changed PWR to BAT+, and added your note, and digital shifter wiring. Did I miss anything else?

 

[cadillackid]

Updated. Changed PWR to BAT+, and added your note, and digital shifter wiring. Did I miss anything else?

love it!!!


make the wire that goes to the AU device from IGN a separate wire fro mthe ignition switch.. otherwise it looks like you are bypassing the switch and T'ing into the battery feed to the IGN switch,,


on the IGN switch you have a BAT+ wire that feeds in, and then you have an IGN+ wire that comes out (only has power when the key is ON).. not sure if there is a ground on an IGN switch or not.. there wouldnt need to be really... ive never actually looked.

 

[nikitis]

love it!!!


make the wire that goes to the AU device from IGN a separate wire fro mthe ignition switch.. otherwise it looks like you are bypassing the switch and T'ing into the battery feed to the IGN switch,,


on the IGN switch you have a BAT+ wire that feeds in, and then you have an IGN+ wire that comes out (only has power when the key is ON).. not sure if there is a ground on an IGN switch or not.. there wouldnt need to be really... ive never actually looked.

Let me check the T444E docs so I can better understand what you are stating. I'll reply back in a few mins.

 

[Bouje bus]

on the CAN side of the AU device, i ordered the model with the 120 ohm load, since i only have the trans TCM on the network. i added a 2nd 120 ohm resistor on a parallel path that is coming off the trans harness ( pair of yellow/ green wires- split to have 2 pairs) so that the TCM is seeing 60 ohm load.

 

[cadillackid]

on the CAN side of the AU device, i ordered the model with the 120 ohm load, since i only have the trans TCM on the network. i added a 2nd 120 ohm resistor on a parallel path that is coming off the trans harness ( pair of yellow/ green wires- split to have 2 pairs) so that the TCM is seeing 60 ohm load.

so the navistar books only show one 120 ohm resistor on the whole J1939 link.. which is how I did mine.. im wondering if the allison TCM's have one built in which would account for only needing one on the ECM side..

 

[nikitis]

I'm having trouble finding a Bat+ in the PDF. Circuit 97C is the "C" port on the J1708, but that's always on, so we don't want to tie into that. Having trouble finding ignition diagram.

There's like 50 items tied to that thing.

97C is a 5V line. So I need a 5V line that is on the Key On correct?

 

[cadillackid]

I'm having trouble finding a Bat+ in the PDF. Circuit 97C is the "C" port on the J1708, but that's always on, so we don't want to tie into that. Having trouble finding ignition diagram.

There's like 50 items tied to that thing.

97C is a 5V line. So I need a 5V line that is on the Key On correct?

'C' on the J1708 port on mine is a +12 VDC tied to the 'DIAG' fuse, i didnt tear apart the thing to read the numbers off of the wires


the IGN switched output shoud provide power to the 'power relay' which is conencted to the ECM.. and likely provides power to a couple other circuits..


the ACC (accessory) out lead goes off to the body-builder plug which handles the main power solenoids for bus stuff like wipers heaters etc

 

[Bouje bus]

i'm still in my infancy learning CAN bus communication.
i found this site to try to build my network.

https://www.terex.com/docs/librariesprovider7/tech-tips/techtip_87.pdf

it calls for 2 resistors and 60 ohm load at the terminal.

is TEREX proprietary or is the IH network on 120 ohm.

 

[nikitis]

So some things I'm trying to understand.
97C is on the same line as 97AA which is also 5V, 97DD is 5V as well.

So Pic below shows C as circuit 97C, and 97C is (5V. Also tied with 97AA and 97BL as 5V.)


So all of these references to 5Volts, for the C circuit.

Then another pic shows C going through Fuse 28, then B+. isn't B+ 12v?

Help me understand this? If the AU Device uses 5V I don't want to send 12V to it and blow it up. (Edit: nevermind. Website for AU device shows PWR +12/24V DC), So if anything it would just be under powered if it weren't 12V.

I guess I can use a volt meter on the two pins to see if it's 5V or 12V.

 

[nikitis]

Ok, I'm getting 12.55V out of that port so it's definitely 12v. I don't understand the diagrams at all then.

 

[cadillackid]

I honestly believe that 5V is a typo in the book.. should be 97CD or such which is a BCC +5 VDC used as a reference for sensors..



97C you can see comes from the battery through a fuse and then to the diagnostic connector

 

[cadillackid]

OK I posted a video demonstrating what happens if you have a failed J1939 running to an electronic allison..


the transmission does NOT LIMP.. but it will run with no lockup and will shift terrible..


since many here dont have access to allison DOC or oter scan tools to watch the transmission link I figured id post this so you get an ideas of how it will act differently with and without that link..



also shows on the single box 444E where the J1939 connector is so you can go look for it to see if you have it native on your bus..


it is imperative when you harness out your setup that you hook up the check trans and the inhibit (if equipped) lights.. I used the 2 pilot lamps on my dash that used to be for the school lights.. yellow for check trans, red for inhibit.


https://youtu.be/qxf-3QTxVeQ

 

[nikitis]

Ok, well we've established that's probably the case. (Thanks International for the misinfo)

Moving on. Can you illustrate crudely so I can understand how i'm connecting the power to the IGN switch. It's the last part I don't get electronically. I just can't wrap my head around it because I don't understand the IGN switch as well as I should.

Or if you have a diagram and can mark where to T into?