Medium and Heavy Trucks

Have truck repair questions? Ask an Expert

Connect one-on-one with {0} who will answer your question

This answer was rated:

I have a 2016 Peterbilt 348 with a PX-9 engine. Allison 3500…

Hello. I have a...

Hello. I have a 2016 Peterbilt 348 with a PX-9 engine. Allison 3500 RDS-P. Vin *****************.

Mechanic's Assistant: What's the make/model/year of your truck? Engine type?

I have a 2016 Peterbilt 348 with a PX-9 engine. Allison 3500 RDS-P. Vin *****************.

Mechanic's Assistant: Are you fixing your truck yourself? What have you tried so far?

Fixing myself. Unit came in from transmission problems. Customer states felt like slipping in all gears. We have Allison DOC software. Was unable to connect with multiple computers. We used cummins insite to commect but only pulled OEM engine codes, data etc. Used Diagnostic link to see if we could pull modules for abs, transmission, body control to no luck. We are only able to see Engine, and Engine retarder modules. I checked my resistance for my J1939 ans was right at the 60 ohms. Before I tackle the transmission issue, I need to see why I am not finding Abs, body control, transmission modules. All wiring, connectors, fuses, relays and circuit breakers are good. We even swapped a sister truck TCM to see if it would connect. No luck.

Mechanic's Assistant: Sometimes things that you think will be really complicated end up being easy to fix. The Heavy Truck Mechanic I'm going to connect you with knows all the tricks and shortcuts.

Thank you

Mechanic's Assistant: Anything else you want the truck mechanic to know before I connect you?

I was able to pull the allison code with the gear selector and pulled P2761. I know that was my original problem, but I need to see why I cannot hook up and see my ABS, Transmission and other modules before I tackle the transmission issue.

Show More
Show Less
Ask Your Own Medium and Heavy Trucks Question
Answered in 56 minutes by:
2/18/2019
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 3 years ago
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,447
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel
Verified

Hello and thank you for contacting us at Just answer. My name is***** allow me to assist you with your issue. The resistance on your 1939 is a quick check, One other thing I would check is the resistance on the high and low to ground. Also check the 1587/1708 link for resistance to ground on each. When you perform your resistance checks make sure that the batteries are disconnected because if any modules are broadcasting any info your resistance reading will read fine but will be incorrect with no power. The voltage measurement should equal around 5v between the high to ground and the low to ground but they should not equal. The usual at KOEO is 2.2-2.35 on the green and 2.6-2.8 on the yellow. As long as you have all the needed resistance, and voltages with no short to ground or power then I would unplug one module at a time to make sure that module is not eliminating messages across the link. Please let me know if you have any other questions on this issue. Thank you and have a nice day.

Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 3 years ago
Thank you. I will do these checks and get back to you.
Customer reply replied 3 years ago
Ok I did the procedures. J1939 pins C and D 60 Ohms. 1587/1708 pins F and G 60 Ohms. Pin D 1.8v to ground. Pin C 2.65v to ground. Pin F 2.7v to ground. Pin G 2.35v to ground.
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 3 years ago

What is the resistance between c to ground and d to ground? Your pins f and g are the 500K baud rate link(iso) if you have 60 ohms of resistance on that link.

Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 3 years ago
My resistance on c to ground and d to ground was open circuit. This was with batteries disconnected. What did you mean by thr 500k bit rate?
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 3 years ago

The standard rate for the base 1939 is 250, This is how many bytes a second the data transmits. The ISO link is the ultra high speed link. This is a power train data link that is usually linked to the aft system, engine ecm, and transmission. So on your Allison doc program you may want to try changing settings around and doing the direct connect instead of the smart connect.

Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 3 years ago
oh ok. I will try that in the morning. Is it a problem that i had open circuit on c to ground and d to ground instead of an ohm reading. ?
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 3 years ago
No that is good. The resistance to ground is usually about 9-100k
Ask Your Own Medium and Heavy Trucks Question
Customer reply replied 3 years ago
Good morning. I will try the allison software high speed link instead of standard j1939. Ill keep you posted. Thanks!
Customer reply replied 3 years ago
Alright I tried the following protocols. J1939, CAN, J1708, J1850, ATEC160BAUD, IESCAN. None of them worked. I rechecked my voltage from A and B i had 12v. I guess I am down to unplugging modules and seeing if i can connect.
Customer reply replied 3 years ago
It seems we lost the whole ISO 1587/1708 data link. How can that be if my resistance and voltages were correct?
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 3 years ago
The iso is a high speed 1939 style link. The 1587 is the older speed link. If the link is down you will still have voltages and resistance reading okay at times because it takes an graph ossicilscope to read the wavelengths to see what module is reading what.
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,447
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel
Verified
Mike Mcmillan and 87 other Medium and Heavy Trucks Specialists are ready to help you
Ask your own question now
Customer reply replied 3 years ago
Oh gotcha. I got it backwards. The customer states they had the ecm reprogrammed a year or so ago. It is a garbage truck and had issues with the engine signals and the pto for the trash box. We are going to contact the company who reprogrammed the ecu. Thank you for your help!
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a technicianLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Mike Mcmillan Your Own Question
Mike Mcmillan
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,447
6,447 Satisfied Customers
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel

Mike Mcmillan is online now

Related Medium and Heavy Trucks Questions
I have a 2012 T 800 Kenworth with automatic. I believe i'm
I have a 2012 T 800 Kenworth with automatic. I believe i'm having trouble with the j1939 comunication harness as i can not communicate with any ecu's ive tried engine, abs, allison , can you tell me w… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
2013 peterbilt not starting. Lights turn on but not the
2013 peterbilt not starting JA: How long have you had problems starting the vehicle? Do any lights still turn on? Customer: lights turn on but not the mileage and rpm JA: What's the make, model, and y… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
I have a 2016 Peterbilt 579 with a Cummins ISX 15 engine and
I have a 2016 Peterbilt 579 with a Cummins ISX 15 engine and Eaton Auto Shift Transmission. When the truck is going down the road pulling a load for a few hours, all of the sudden the traction control… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
I have 2011 peterbilt with cummins isx and autoshift
I have 2011 peterbilt with cummins isx and autoshift transmission, sudenly get the code J1939 and truck stops … read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
I have a 2016 pete 348 with codes U0103 and U0073. I'm
I have a 2016 pete 348 with codes U0103 and U0073. I'm inclined to resolve the U0103 gear shift module first, since it may be causing the general CAN fault. I don't know where any of the modules are o… read more
Andrew G.
Andrew G.
Heavy Truck Mechanic
Heavy Duty Equipment - Truck and Transport Mechanic
4 satisfied customers
Working on a 12 Peterbilt with a DD15 engine #79612011 ISX15
Working on a 12 Peterbilt with a DD15 engine #79612011 ISX15 ModelWe are trying to connect to ECM using the Cummins insite 8.7 with a Nexiq link 2 but it will not connect saying error not sure how rec… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
If you can help me I have a piterbilt cummins year 2020 the
Hello there, if you can help me I have a piterbilt cummins year 2020 the selector shows 2 xx and the DEF clock does not mark and only tab the red light of the clock I put the computer and it has 2 cod… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
I'm working on a 2001 Kenworth t300, with a cat 3126 and an
I'm working on a 2001 Kenworth t300, with a cat 3126 and an Allison trans. I have a crank no start situation and am unable to communicate with the ecm.… read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
2014 Peterbilt 337 6.7 L 408 L6 PACCAR PX-7 Diesel 268189
2014 Peterbilt 337 6.7 L 408 CID L6 PACCAR PX-7 Diesel 268189 milesoriginal customer complaint: limp mode wont go over 40mph.what has been done: FOUND CHECK ENGINE LIGHT ON FOUND THE FOLLOWING ACTIVE … read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
2016 freighter Cascadia with Allison transmission. Truck was
2016 freighter Cascadia with Allison transmission. Truck was running without issues until today it is setting 2 transmission codes: spn 40 fmi 5 and spn 2003 fmi 31. Any experience with this? Consider… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
2014 VOLVO VNL 730 ISX15 I HAVE CODE 3528, SPN 558, FMI 9,
2014 VOLVO VNL 730 ISX15 I HAVE CODE 3528, SPN 558, FMI 9, ACCELERATOR PEDAL /LEVER IDLE VALIDATION SWITCH (IVS) UPDATE RATE ABNORMAL. CODE 3326, SPN 91, FMI 9, J1939 MULTIPLEX ACCELERATOR PEDAL LEVEL… read more
Joel Bos
Joel Bos
909 satisfied customers
Can I please get information on valve setting procedures for
Hello, Can I please get information on valve setting procedures for a Paccar PX-9 engine, please? … read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
Looking for w900 data link wiring schematic for the Kenworth
Looking for w900 data link wiring schematic for the Kenworth side not the Cummins side … read more
Nich1019
Nich1019
Diesel Technician
Vocational, Technical or Trade School
55 satisfied customers
Spn 973 spn 563, abs light, assist light, check trans light
Spn 973 spn 563, abs light, hill assist light, check trans light happens when I hit bumps … read more
Expert
Expert
10,510 satisfied customers
I have a 2017 peterbilt 348 vin 200010 I'm getting a fault
I have a 2017 peterbilt 348 vin 200010 I'm getting a fault that says on the dash, relay diagonal 1. My diesel laptop computer is not reading the abs module. Do I have 2 repair issues here? Or what am … read more
Keiphun Sowell
Keiphun Sowell
Owner Brothers Restoration/Troubleshoot
AutoDiesel Technology
2,574 satisfied customers
I have a 2015 peterbilt 579. It is having regen issues. I
I have a 2015 peterbilt 579. It is having regen issues. I pulled apart the decomposition tube( I found def crystals at dosing valve. There was solidified def in the decomp tube, I cleared all that out… read more
Andy
Andy
truck /coach technician
Vocational, Technical or Trade School
214 satisfied customers
I have a KW T800, Cummins ISX CM570, Allison 4500 RDS, cruise
Hi I have a KW T800, Cummins ISX CM570, Allison 4500 RDS, cruise control & engine brake not working. I have checked the engine brake & wiring harness from ECM to brake working fine when voltage applie… read more
Andy
Andy
truck /coach technician
Vocational, Technical or Trade School
214 satisfied customers
i have a 2004 Volvo with an isx st2 last 6 of vin is 371735.
hi i have a 2004 Volvo with an isx st2 last 6 of vin is 371735. it has not throttle response codes displayed are check light control module check ecm and check ecm data link connector. was told custom… read more
cumminsdr
cumminsdr
Mechanic
High School or GED
1,886 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

Daniel Wilson

Daniel Wilson

6,062 satisfied customers

Owner at DJ Wilson

Cat Man

Cat Man

Cat Engine Expert

5,353 satisfied customers

I am ASE Master Truck Certified.

Wayne

Wayne

Journeyman

5,115 satisfied customers

worked on, Gmc, Macks, Freight liner,Mercedes Benz,,Ford, sterling

Jeremy

Jeremy

Certified Truck/Bus Technician

2,756 satisfied customers

ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, Network Engineer specializing in CAN faults, Aftertertreatment, and vehicle communications

Curtis B.

Curtis B.

Technician

1,947 satisfied customers

Technician turned service manager on multiple lines of trucks and engines, used in industry.

cumminsdr

cumminsdr

Mechanic

1,886 satisfied customers

All types of Cummins applications

Chris (aka-Moose)

Chris (aka-Moose)

Technician

641 satisfied customers

24 years of experience diagnosing & repairing

< Previous | Next >

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x