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Precaution of Troubleshooting for CAN




Precaution of Troubleshooting for CAN

CAN schematic and routing diagram














Outline of troubleshooting

When there is a trouble with CAN, perform Symptom Related Diagnostic Procedures Troubleshooting for Communication Error with Scan Tool Using CAN
and/or Initial Inspection and Diagnostic Overview Troubleshooting for CAN-DTC. Not using this procedure or performing troubleshooting in any other way may skip some check points resulting in misdiagnosis or take a longer time than necessary.
1) Checking connector related to CAN
2) Checking CAN line
3) Checking each control module/sensor using "DTC check" or "Bus Check"
4) Checking power and ground connection of each control module/sensor

CAN-DTC

Even when DTC related to CAN (= CAN-DTC) as described below is detected, it is not possible to point out the specific trouble point by CAN-DTC itself. Be sure to troubleshoot according to Initial Inspection and Diagnostic Overview Troubleshooting for CAN-DTC.

CAN-DTC table






Communication with scan tool

- K line or CAN line is used for communication between each control module and scan tool.
Refer to CAN schematic and routing diagram
to determine which line is used for communication between each control module and scan tool.
- ECM, TCM, BCM and SDM use CAN line for communication with scan tool. Even if CAN has a trouble other than between DLC and BCM, communication may also fail between scan tool and these control modules. In such case, perform troubleshooting according to Symptom Related Diagnostic Procedures Troubleshooting for Communication Error with Scan Tool Using CAN.
- ESP(R)/ABS control module, 4WD control module use K-line for communication with scan tool. Even if CAN has a trouble, it is possible to communicate between scan tool and these control modules.

Bus check with SUZUKI scan tool

SUZUKI scan tool (SUZUKI-SDT) efficiently diagnoses a CAN bus malfunction by "Communication Bus Check" and "Communication Malfunction DTC" under "Bus check".

"Communication Bus Check" can display all control modules/sensors name communicated by CAN.