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Principles Of Operation




Smart Junction Box (SJB)

Principles of Operation

NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).

The SJB receives inputs and delivers outputs to electronically-controlled features of the vehicle. The SJB constantly monitors the systems under its control and reports a concern in the form of a DTC. The DTC can be retrieved with a scan tool through the Medium Speed Controller Area Network (MS-CAN).