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Bluenozer
Advanced Member

Canada
484 Posts

Posted - 10/15/2021 :  10:39:11 AM  Show Profile  Reply with Quote
2011 C2 ISB Wabco air brakes
LCD states No Engine
BHM 164
Only codes are BHM codes- wheel based speed CAN error
- wheel speed-network data error
At every place that you can test J1939 I have 60ohms
At every ECM(BHM,CHM,ECU)- all have good power and ground and tested with a headlamp
We have a junked C2 R&R an ECM one at a time no change
R&R all ECMs again no change
Followed a service bulletin from Carolina Thomas for testing data links - all in spec
Service link Data trouble shooting 54.19 all ohms and voltages are in spec except for J1587 HIGH and LOW to ground, states should be more than 1K ohms and on both I get .8K ohms
Could a bad ICU or ABS ECU cause this the only thing that I didn't try to swap but why NO ENG from these , maybe ICU
Engine will not even crank over
all interior features are operational(fans,lights,window buzzers, etc.)
When you turn on the ignition there is no modulator chuff either , but at the ABS ECU - powers,ignition power,ground and data links are testing to spec and the lap top hooks to it
LOL any ideas got about 6 hrs into this one
Thanks for reading and could not get service link to fire up , anyone still get service link to work


Edited by - Bluenozer on 10/15/2021 10:42:32 AM

buster133
Top Member

USA
509 Posts

Posted - 10/17/2021 :  2:46:22 PM  Show Profile  Reply with Quote
Last unit I had with this issue it was corrosion underneath the fender mounted fuse box. It was isolated to the 3 larger fuses on the back half of the box

[URL=http://s7.photobucket.com/user/buster133/media/6f2e0703-1970-4ac9-bb1f-b6b9d7c12297_zps1741e113.jpg.html][/URL]
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Gearbox
Active Member

USA
46 Posts

Posted - 10/18/2021 :  10:39:21 AM  Show Profile  Click to see Gearbox's MSN Messenger address  Reply with Quote
Document that addresses BHM diagnosis.
http://ww2.justanswer.com/uploads/ClaytonH729/2010-09-28_135818_518_sb54177.pdf?r=impact%7C2003851%7CBlogger.com%7C&clickid=QrkUSiX4zxyOUPr0RHQK3XRkUkBSX9URRVaHzk0&aff_sub_id=EdgeBingFlow&aff_sub_id2=oc5A05L8E%2FcFrofF6SHThDugLUNdxgjRxGygTKcCgYZHUrn1eqdnNO2MJAyPvhCa&aff_sub_id3=&aff_sub_id4=&irgwc=1
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Bluenozer
Advanced Member

Canada
484 Posts

Posted - 10/19/2021 :  02:28:07 AM  Show Profile  Reply with Quote
Thank you both , I will be travelling to the depot that has this unit, real issue is that servicelnk will not fire up, but we have Jpro and it hooks to everything and shows everything except for the engine, and these two wheel speed codes in the BHM , but with wabco there is no issues with the brakes

OEM trained in wiring and all engine platforms for 20 years
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Bluenozer
Advanced Member

Canada
484 Posts

Posted - 10/19/2021 :  09:15:23 AM  Show Profile  Reply with Quote
Checked that stuff, thanks again, no issue in the PDM , and still 4 laptops and servicelink does not load up , going to try another ICU from a sister unit, heres the exact script at the end of my trouble shooting- crack a beer for this-
These roll call faults indicating the engine is not detected by the ICU on the J1587 datalink. This does not indicate an ICU problem, NOR does it indicate a J1587 datalink problem to the ICU
Engine back bone is good at 60ohms also

OEM trained in wiring and all engine platforms for 20 years
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671Fan
Active Member

40 Posts

Posted - 10/19/2021 :  10:21:00 AM  Show Profile  Visit 671Fan's Homepage  Reply with Quote
Try disconnecting other modules on the data link one at a time and see what happens. We had a TCM that failed and fouled the data link. Disconnected it and everybody else was able to communicate again.
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Bluenozer
Advanced Member

Canada
484 Posts

Posted - 10/19/2021 :  10:38:11 AM  Show Profile  Reply with Quote
done that , and replaced all modules with good tester modules, even the engine ECM(one at a time and then all at once also) , and the engine is the module that hasn't shown up to the data link party , got it crnking today though(exciter wire was bad on the top of the transmission), can only put about 2 hrs a day on it for I have to be present out here for the bus runs
thank you for your idea will take a and all right now

OEM trained in wiring and all engine platforms for 20 years
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Bluenozer
Advanced Member

Canada
484 Posts

Posted - 10/20/2021 :  02:34:39 AM  Show Profile  Reply with Quote
ok service literature 54-12 page 410/1 states my two BHM codes are transmitted from my engine ECU on EPA 07 and older engines(which this is EPA 07)

OEM trained in wiring and all engine platforms for 20 years
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Bluenozer
Advanced Member

Canada
484 Posts

Posted - 10/21/2021 :  02:26:37 AM  Show Profile  Reply with Quote
found nothing, sending it to the stealership(that i used to work at before here) when the service writer seen me with all my paper work, he asked if they could burn it lol , they still call me for wiring help :( , so they are starting with the phone call to DTNA help line
my luck I over looked a simple solution , and if I did it won't happen again lol

OEM trained in wiring and all engine platforms for 20 years
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td083
Senior Member

194 Posts

Posted - 10/25/2021 :  08:28:56 AM  Show Profile  Visit td083's Homepage  Reply with Quote
I had one similiar to this i think it was a amtran ce with a maxxforce dt 2009 , sent me in circles checking the can system swapping out ecus and so on , we sent it out they stated it was likely struck by lightning and replaced every module in the bus , ecm , tcm , bcu abs and what not , to fix it
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Bluenozer
Advanced Member

Canada
484 Posts

Posted - 10/27/2021 :  07:45:53 AM  Show Profile  Reply with Quote
They found it, the one ignition wire I over looked , pin 45 in the OEM side of the ECM, tested the 5A fuse but never tested for power at the plug , well I'll be dipped lol

OEM trained in wiring and all engine platforms for 20 years
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