Computers/Controls - CAN Communication Diagnostic Information
Classification: EL13-007A
Reference: NTB13-027A
Date: August 22, 2013
2005-2013 NISSAN;
CAN COMMUNICATION - NETWORK DIAGNOSTIC FLOW CHART
Bulletin amended to change End Diagnosis 5 to 4 and End Diagnosis 6 to 5. No other changes have been made to the body of this bulletin. Discard previous versions.
APPLIED VEHICLES: All 2005 - 2013MY Nissan Vehicles
SERVICE INFORMATION
This TSB is for troubleshooting of CAN Modules with "Diag-On-CAN" Diagnostics. The flow charts below are meant to troubleshoot current CAN DTCs. The flow charts are intended to diagnose one module at a time; repeat the process as needed for additional control units.
Definition of CAN Codes:
U1000 - missing ECM CAN communications not related to OBD2 system
U1000 - missing CAN communications for all other ECUs
U1001 - missing ECM CAN communications related to OBD2 system
U1002 - similar to U1000, but has a tighter timing spec to set the DTC
U1010 - Module has internal Issues
CLAIMS INFORMATION
Helpful Tips:
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Always diagnose CAN communication codes first, U1000, U1001, U1002, U1010, then network codes, UXXXX, and then all other codes.
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A quick method to test CAN communications is to operate the vehicles functions such as Hazards, Brakes, Tachometer, PRNDL, Speedometer, 4WD, Difflock, Seat Memory, Power Back Door or High Beams.
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In a low voltage situation (less than 10V), modules will stop communicating at different voltages.
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Integrated Power Distribution Module (IPDM) is a smart relay and fuse box. It powers other modules in the same way fuses and relays do.
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CAN voltages can be checked via CONSULT.
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Missing "Ignition 2" fuse or other high level fuses can cause CAN Diag Support Monitor to not work.
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High level fuses such as "Ignition 1", "Ignition 2" and "Elec B" power many modules.
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Pins/terminals can be bent and still pass visual inspection.
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When troubleshooting a harness that has multiple inline connections, section off the harness and isolate it one portion at a time. Add a terminating resistor to the end of the harness in substitution of the terminating modules.
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If a module has multiple connectors, disconnect one at a time.
NOTE:
120 ohm resistors may be needed to perform diagnostics.
Normal CAN Measurements
Main Types of Issues
NOTE:
Use legend below for flow charts and Table A.
