Classification:

Reference:

EL10-017C

Date:

NTB10-066C

May 20, 2024

CAN COMMUNICATION CODES – DIAGNOSTIC TIPS AND
GUIDELINES
This bulletin has been amended. See AMENDMENT HISTORY on the last page.
Please discard previous versions of this bulletin.

APPLIED VEHICLES:

All 2005-2024 Nissan vehicles except:
 2023-2024 ARIYA (FE0)
 2022-2024 Pathfinder (R53)
 2021-2024 Rogue (T33)
 2020-2024 Sentra (B18)

SERVICE INFORMATION
Related to communication codes U1000, U1001, U1002, U1010:


Always diagnose the communication codes first.



When a module reports a U1000 code, it is typically operating normally;
however, there is a communication error external to that module on the CAN
network.



U1000 indicates an error. V-CAN diagram or CAN Diag Support Monitor
provides data to determine the location of the error.

Step 1
Complete the CAN diagnosis with CONSULT-III plus (C-III plus).


Ensure the correct CAN type is selected. Selecting the incorrect CAN type will
lead to mis-diagnosis.

Step 2
View the V-CAN screen (shown on page 3) or print all CAN Diag Support Monitors
(shown on page 4).
Nissan Bulletins are intended for use by qualified technicians, not 'do-it-yourselfers'. Qualified
technicians are properly trained individuals who have the equipment, tools, safety instruction, and
know-how to do a job properly and safely. NOTE: If you believe that a described condition may apply to
a particular vehicle, DO NOT assume that it does. See your Nissan dealer to determine if this applies
to your vehicle.
1/14

Step 3
Read the V-CAN diagram using the key provided OR reference the appropriate
Electronic Service Manual (ESM) to analyze the CAN Diag Support Monitor data.
Determine the incident according to the display.
Step 4
If V-CAN diagnosis is not available or inconclusive, refer to the basic CAN diagnostic
guidelines shown on pages 6-13. These represent electrical values of the CAN system
measured at the Data Link Connector or connectors at non-termination units.
To properly perform these basic checks:


The battery should be disconnected for resistance checks.



The ignition should be OFF.

Tips if a control module is the suspected root cause:


Improper module configuration or incorrect part numbers may set CAN DTCs.



Low battery voltage may set CAN DTCs.



Always confirm the power, ground, and CAN resistance at a suspect module
before replacing the module. Resistance should be close to 60 ohms at the
module (measured with the battery disconnected). The resistance at
terminating modules should be close to 120 ohms. Examples of terminating
modules include IPDM, ECM, or BCM. Reference the appropriate ESM to
determine the terminating modules.

DEFINITION OF CAN CODES
U1000 is related to missing CAN communications on the network.
U1001 is for Engine Control Module (ECM) and is related to missing CAN
communications on the network.
U1002 is related to missing CAN communications on the network but has a tighter
spec than U1000.
U1010 - Module has internal errors.

2/14

NTB10-066C

V-CAN Diagram Screen
Step 3 Illustration

TCM

Red = Current Communication Error
Orange = Past or Intermittent Communication Error
Black = Not Diagnosed
Green = Normal Operation
Pink = Module Error
HINT: If a module is highlighted in pink when other modules or segments are highlighted in red or orange, perform diagnosis
on other modules, erase DTCs, and run Auto CAN diagnosis with C-III plus again. If module is still highlighted in pink,
replace module.
3/14

NTB10-066C

CAN Diag Support Monitor
Step 3 Illustration

Print Example

HINT: These prints are needed for
ESM CAN Diagnosis or if the
V-CAN diagram diagnosis is not
available.

4/14

NTB10-066C

DLC Breakout Box J-51513
When performing any pin testing of the CAN
systems at the DLC (Data Link Connector),
“DLC Breakout Box” J-51513* should be
used.


Plug the DLC Breakout Box into the
vehicle DLC connector and perform all
voltage, resistance and continuity
testing directly from the provided “pinouts” shown in Figure 1.



Do not connect the CONSULT PC to
this tool. Although it does have a port
to do so, the tool currently does not
support this function.



Front of DLC Breakout Box
Figure 1

Do not jumper the “Battery Power”
pin-out to either of the ground pinouts.
Damage will occur.



All pin-out locations are marked in
accordance with their associated DLC
connections and will allow convenient
pin testing of the DLC connector.



Figure 2 shows the back of the DLC
Breakout Box, and has a legend of the
DLC pins.

DLC legend

Back of DLC Breakout Box
Figure 2



Figure 3 shows Banana leads that are
supplied with the DLC Breakout Box
and are used to connect to a DVOM.
HINT: 48” Banana Leads
(J-35616-20W) are available and are
sold separately.

*Use “NI-51513A” if ordering from Tech•Mate
(www.techmatetools.com/1-833-397-3493).

5/14

Banana test leads
Figure 3
5/14

NTB10-066C

HINT: Diagram shown with terminal resistor in IPDM. The vehicle that you are working on
may have the terminal resistor in the BCM. Refer to the ESM for additional information.

Battery is Possibly
Connected - disconnect and
recheck resistance

120Ω

120Ω
#14 CAN Low
Data Link
Connector

6

>1 KΩ

#6 CAN High
14

Plug “DLC
Breakout Box”
J-51513 into
DLC
6/14

HINT: Check the ESM wiring diagrams for DATA
LINK CONNECTOR to confirm pin outs for CAN
circuits. Aside from PIN #6 (CAN-H) and PIN
#14 (CAN-L), other pin outs could be designated
for secondary CAN systems (i.e., M-CAN).
NTB10-066C

HINT: Diagram shown with terminal resistor in IPDM. The vehicle that you are working on
may have the terminal resistor in the BCM. Refer to the ESM for additional information.

Normal Resistance –
CAN Harness

120Ω
120Ω

120Ω

6
#14 CAN Low

60 Ω

If measured with
terminating module
disconnected,
Resistance = 120 Ω

Data Link
Connector
14

#6 CAN High
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NTB10-066C

HINT: Diagram shown with terminal resistor in IPDM. The vehicle that you are working on
may have the terminal resistor in the BCM. Refer to the ESM for additional information.

Normal Resistance –
CAN High to Ground

120Ω
120Ω

120Ω
120Ω
120Ω

#14 CAN Low
6

4
Data Link
Connector

1K Ω -OL
#6 CAN High
HINT:
• OL= Open Circuit
• Expect OL if battery negative cable is connected
• Expect 1.0KΩ – 1.2KΩ if battery negative cable is disconnected
8/14

NTB10-066C

HINT: Diagram shown with terminal resistor in IPDM. The vehicle that you are working on
may have the terminal resistor in the BCM. Refer to the ESM for additional information.

Normal Resistance –
CAN Low to Ground

120Ω

120Ω

#14 CAN Low
4
Data Link
Connector

1K Ω -OL
#6 CAN High
14

HINT:
• OL= Open Circuit
• Expect OL if battery negative cable is connected
• Expect 1.0KΩ – 1.2KΩ if battery negative cable is disconnected
9/14

NTB10-066C

HINT: Diagram shown with terminal resistor in IPDM. The vehicle that you are working on
may have the terminal resistor in the BCM. Refer to the ESM for additional information.

Open CAN Harness

120Ω

120Ω

#14 CAN Low

6
Data Link
Connector

120 Ω
14

#6 CAN High
10/14

NTB10-066C

HINT: Diagram shown with terminal resistor in IPDM. The vehicle that you are working on
may have the terminal resistor in the BCM. Refer to the ESM for additional information.

Short – CAN High
to CAN Low

120Ω

120Ω

#14 CAN Low
6
Data Link
Connector