IK0800080 ­ 1939 Data Link Troubleshooting

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Document
IK0800080
ID:

Availability:

ISIS, Bus ISIS, FleetISIS, Body Builder

Revision:

7

ELECTRICAL SYSTEM

Created:

8/22/2007

English

Last
Modified:

10/1/2014

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Author:

Joe
Christopher

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Title : 1939 Data Link Troubleshooting
Applies To : All models

Change Log
Dealers: Please refer to the change log text box below for recent changes to this article:
10/01/2014 - Service Information (Known Issues) section updated to include faults that may occur due to
connecting with the EZ-Tech Launcher
10/01/2014 - Troubleshooting revised to Step­Based Diagnostics. Article layout revised. Table of Contents
added for better navigation.
06/06/2014 - New information of a possible failure found through the case file system has shown us a
potential failure location. Refer to the new "Service Information" section.




• You MUST review the "Service Information (Known Issues)" section of this iKNow article PRIOR to troubleshooting anything on the truck.

Table of Contents
Description

Service Part(s) Information

Symptom(s)

Additional Resources

Special Tool(s) or Software

Connector Views

Diagnostic Steps

Service Information (Known Issues)

Description
There are a few things that you need to understand before troubleshooting the 1939 data link.
1. First, the drivetrain J1939 data link, J1939 body builder data link, and J1939 engine data link are three completely separate data links.
◦ For specific examples of modules on each different data link Click Here
2. The different J1939 data links work the same way, but the wiring for them is not connected.
3. The troubleshooting below is geared towards the drive train J1939 data link, but the same principles apply to the body builder and engine
data link.
4. The J1939 data link consists of a twisted pair of yellow and green wires that all the modules on the truck use to communicate with each
other.
5. Two 120 ohm terminating resistors are wired in parallel on the data link. Total resistance on a properly working data link is 60 ohms.
6. When you are checking the data link, if the problem is not present, the data link will show good.
7. The J1939 data link may be referred to as data bus, or CAN as well.
8. A module is capable of being connected to the public and private data link, but the information remains separate.
◦ Example: The Body Controller communicates on the drivetrain data link, but also has the body builder data link wired to it.
◦ Example: The EIM communicates on the drivetrain data link, but also communicates with the ECM and ACM on the engine private
data link.
For Post‐2007 vehicle 1939 troubleshooting, click on the appropriate link below:

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlI...

11/3/2014

IK0800080 ­ 1939 Data Link Troubleshooting

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• The troubleshooting cards give a good overview of the data link. This will help show you the backbone of the data link (main data link
wiring between 1st terminating resistor to 2nd terminating resistor) and the stubs of the data link (wiring from the backbone to each
possible module)
Basic example of Public J1939 data link

• The J1939 Splice Adapters (1024, 1025, 1026) are part of the backbone of the data link (The backbone will come in on 2 terminals and
leave on 2 different terminals). The wiring from the connector to each module is a stub.
◦ HPV (medium duty) 1939 Troubleshooting Card
◦ CE / BE Bus 1939 Troubleshooting Card
◦ ProStar 1939 Troubleshooting Card

These cards are 11" x 17" so they may not print well on regular size paper.
If you wish to order the above cards, you can order them through the Navistar Print Portal from the Service Portal ‐ Dealer Menu. The part
numbers are:
Vehicle Model

Part Number

ProStar Card

S00153

DuraStar, TranStar & WorkStar Card

S00155

CE / BE Bus Card

S00154

( Back to Top )

Symptoms
Diagnostic Trouble Code(s) & Dashboard Indicator Light(s):
SPN

FMI

Module and Source Address (SA)

Description

639

9

Body Controller (33)

Drivetrain message timeout

639

14

Body Controller (33)

Drivetrain message timeout

2000

19

Body Controller (33)

PTC1 (PGN 64892) not Received from Engine

2023

9

Body Controller (33)

EGC data link communication failure

2000

9

Gauge Cluster (23) / Body Controller (33)

Loss of data link from the Engine Controller

2003

9

Gauge Cluster (23) / Body Controller (33)

Loss of data link from the Transmission Controller

2011

9

Gauge Cluster (23) / Body Controller (33)

Loss of data link from the ABS Controller

2023

14

Gauge Cluster (23)

Gauge cluster lost communication with the ESC

2023

14

Gauge Cluster (23)

Gauge cluster lost communication with the Engine Controller

2033

9

Gauge Cluster (23)

Loss of data link from the ESC

560

19

Engine (0)

Transmission driveline engaged not detected on J1939

609

19

Engine (0)

ACM not detected on J1939

https://evalue.internationaldelivers.com/service_kb/DocTool/ArticleViewer.aspx?ControlI...

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IK0800080 ­ 1939 Data Link Troubleshooting

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639

14

Engine (0)

J1939 data link error (ECM unable to transmit)

639

19

Engine (0)

J1939 data link error (ECM unable to transmit)

Customer Complaint(s):
•
•
•
•

Gauges inoperative (Constant or Intermittent)
Transmission will not go into gear
Warning Lights
Check Electrical Message

( Back to Top )

Special Tool(s) or Software
Tool Description

Tool Number

Comments

INTUNE

EZ‐Tech Software

Helios

EZ‐Tech Software

Diamond Logic Builder (DLB)

EZ‐Tech Software

ServiceMaxx

EZ‐Tech Software

Fluke DVOM

ZTSE4357

Digital Multimeter

Electrical Tester

ZTSE4858

180‐Pin Breakout Box

00‐00956‐08

Breakout box allows for testing engine control module and body control module systems

Breakout Harness Kit

Multiple

Use breakout harness that is applicable to the system you are testing

Terminal Test Kit

ZTSE4435C

Kit, Int. Elec. Eng. Terminal Test

Terminal Test Kit

77066‐nav

Hickok Break‐Out Tee Builder And Pin‐Out Tool

( Back to Top )

Diagnostic Steps

• The problem must be present when taking these readings!!
• If the problem is NOT present, the reading will be within spec every time!!
The diagnostic checks listed below can be performed at any module connector
• Making checks at each module connector can help isolate a voltage drop / increase in resistance / short to power or gound
• Use the worksheet below to identify which modules, connectors and terminals you have checked
Connector Terminal Worksheet
• This can also help identify if the J1939_High and J1939_Low wires are pinned incorrectly at a connector
Step

Action

1

• Install a comm. device (Nexiq USB, NavCom, NavLink) the
Power LED should be illuminated.
Is the Power LED illuminated?

2

Decision

Yes: Continue to Step 2
No: Verify proper power and ground to the 9‐pin ATA diagnostic
connector
Yes: Obtain screen shot or record all modules. Continue to Step 3

• Install a scan tool.
• Turn the ignition key on, engine off (KOEO).
• Attempt to establish communication with INTUNE.

No: Continue to Step 6

Are you able to communicate with any of the modules?

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IK0800080 ­ 1939 Data Link Troubleshooting

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Note: Refer to IK0800351 to indentify the module to the source
address.
Yes:

3

• Evaluate modules detected on the sniffer.
Can you identify a module that is NOT communicating?

• Check the fuse for that module.
• Load test the battery power, ignition power, ground circuits at
the module connector.
• If ALL power and ground circuits test okay, test the data link
circuits at that module connector using the information
starting at Step 6.
• Repair wiring as needed to allow the module to communicate
on the data link and re‐test the system.
No: Continue to Step 4

4

• Check for Diagnostic Trouble Codes (DTCs)
Are communication DTCs present in any of the modules?

Yes: Obtain a screen shot of the DTCs in ALL modules (ECM, ABS,
TCM, BC, etc....). Continue to Step 5
No: Evaluate complaint to determine if a data link issue is present.
Determine if faults were previously cleared.
Yes:

• Evaluate fault counts by modules
5
Do one (or more) modules show high fault counts of loss of
communication fault (Other modules would have low counts)?

• Load test the battery power, ignition power and ground
circuits at the module connector.
• If ALL power and ground circuits test okay, inspect the stub
wiring from the module connector to the backbone of the data
link.
• Ensure all terminals are properly seated and fully locked in the
connector.
• Inspect for spread terminals using a terminal test kit to pin
drag test the terminals.
• Verify the wires are pinned properly in the connector for High
(+) and Low(‐).
• Use the information starting at Step 6 to assist.
• If an issue is identified and repaired, re‐test for the complaint.
• If no issue is identified, continue to Step 6
No: Continue to Step 6
Yes: Continue to Step 7

6

No: Continue to Step 8
• Measure the voltage at the ATA Diagnostic Connector
Terminal C to Gnd and D to Gnd.
Is there approximately 2.5 Vdc at each terminal?

7

Does the voltage on C and D match?
Note: Terminal C should have slightly higher voltage than
Terminal D.
Note: The voltages should not match

Yes:
• A module not communicating can put 2.5Vdc on each data link
wire.
• Monitor voltage at the 9 pin diagnostic connector while
unplugging modules
• If the voltage changes and communication resumes suspect an
issue at that module
◦ Load test the battery power, ignition power and ground
wiring to that module
◦ Inspect the data link stub from the module connector to
the backbone