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Diagnostic Trouble Code Repair Sequence

Identify communicating ECU's and any DTC's and their status and category? 

Use the scan tool to communicate with all ECU's.

Create a diagnostic report by recording/capturing the following information, this information can be generated by the "Record Vehicle Scan" report on the "Health Check" page within WTS.

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G16022881Courtesy of VINFAST, LLC

Recording this information is the first step in the Diagnostic trouble code (DTC) repair sequence this information will then be used to complete the rest of the repair sequence and repair verification.

In support of this the technician will need to manually verify if any ECU not communicating with the scan tool is actually built into the vehicle. If a present ECU isn't communicating, then identify which communication BUS the ECU uses to communicate with the scan tool and investigate any faults with this communication system.

While a faulty ECU or communication BUS can cause a lack of communication with one or more ECU's in the vehicle, as long as at least one ECU is communicating then continue on to the next step of the diagnostic trouble code repair sequence as these faults will be addressed in later steps.

Refer to the following service information or technical bulletins for further information: