Pete
Last winter I replaced my 3406E for a C-15 Cat engine in my 1999 Pete 359. Everything went pretty smooth, changing the wires for ECM plug was a little trouble but not bad. (I spent more time trying to get the sob'in fuel system primed) The one issue that I have not resolved is the ABS light. It was not on before the engine swap and now it is, all the time.

I've called some local truck shops and they just want me to bring the truck in.

I'm thinking that the ABS conroller is looking for a signal of some kind from the engine.

If anybody has any ideas or more knowledge on the ABS systems innerworking I would appreciate any info. Thanks

Pete

The ABS will have to communicate with the engine. With all the wiring it is possible the datalink was severed to the ABS module. Or some ABS wiring was damaged during the engine swap, or the module is not powering up. If you have a Bendix system it will have lights on it to say what the code is. There may also be a ABS diagnostic switch somewhere that will start a blink code sequence. If you can get the make, and blink code we can help more, but other than that you will likely need to get a computer on it to see.

Friend, with the light on, it stands to reason that there is a code stored in the ABS computer. If you can find a way to read the code, you'll be well on your way to fixing this problem. It very well might indicate a bad (read: missing) connection, or some other overlooked problem.

I'd goto the shop just to let them hook it up and tell me what it means. Kinda sucks you cant just pop into an AutoZone and get your codes read for free like a four-wheeler. I dont know how many times that has saved me a ton of $$$.

Just my .02

Is your Jake Brake enabled and working? When mine was disabled I got ABS light (and no ABS functioning of course). The way Bendix computers are is that when they smell any trouble communicating with engine ECM they shut off, so Bendix can't be responsible for accidends and all since their system can't work the way was designed

So there is surely more probable reasons that jake - you might try calling them at 800 247-2725 then 2 (technical assistance)

It's more than likely the Powertrain Data Link is not set correctly in the customer parameters in the ECM. If I remember correctly the earlier engines used both a J1922 & J1939 setting in the ECM. A C-15 would only be set to J1939 in the parameter. Depending on the flash file date you should be able to reset this. If you have a newer file than it may automatically default to the J1939. If this happens you may have to reflash the ECM with an older file.

This Powertrain Data Link is what's used to communicate between the truck ABS and the ECM. If this isn't set correctly you will have an ABS light come on.

Dam Computers....LOL

__________________
SHREK

Wow Thanks for all the responses.

The Jake does work very well.

I looked back at my notes/conversion wiring diagram and I have J1939 and the J1922 data links pin locations from the old 3406E plug going no where in the C15 plug.

I think I need to take another look at my harness. I do remember leaving 2 wires folded back and not plugged into the harness/ecm plug. Can't remember why now.

The diagram for the 3406E shows J1587, J1922 and J1939 data link, but C-15 diagram only shows J1587 and J1939.

Got some coffee in the system now, and I remember why I folded the to wires back.
The 2 wires I left out were unplugged from the J1922 Pins in the 3406E 40 pin plug. The C15 plug diagram did not have corresponding J1922 pins in the 70 pin plug. Because I had no absolute position for these I left them out. I figured if they were important something would let me know.
The J1939 data link pins were not used on the original 3406E in my truck.

Can I plug the J1922 data link wires into the J1939 Positive an Negative pins, leaveing the shield pin empty or is is think still going to have to be re-flashed??

In looking back at all my notes and stuff, I found a sheet a paper from the salvage yard where I bought the engine that listed some info/parameters they retreived from the ECM.
#49 ABS Off Road Function Switch, value set to OFF.

Thanks again for all the replies, I may get this problem fixed for cheap yet.

J1939 Data Link Positive is pin 50

J1939 Data Link Negative is pin 34

J1939 Data Link Shield in pin 42

J1922 Data Link Positive is pin 1

J1922 Data Link Negative is pin 14

J1587 Data Link Positive is pin 8

J1587 Data Link Negative is pin 9

In the ECM you will have to program the customer parameters for the Data Links properly after you've wired the truck correctly. If you cannot select both the J1922 and J1939 option you'll have to reflash the ECM with an older flash file that will allow you to select this option in the program. I'm not 100% sure of this, but this is what I'm thinking is the problem. The newer flash files will not allow you to pick this option, they do it for you and this creates a commincation problem with some trucks, but not all trucks. Get the wiring done first and try to change the parameter in the ECM to see what happens.

I haven't looked at the truck yet, but according to my notes pin 1 & 14 are blank. So I will take the 2 wires I left out, plug them in to sockets 1 & 14 and there should be a chance it may work, otherwise I need to have the ecm flashed.

This sounds very promiseing, Thanks for the info and I will let yoiu know next week.

Pete