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Home >> Kia >> 2012 >> Optima LX, Automatic Trans >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 50 (Body Control Module Diagnosis - HEV) >> DTC B1603: CAN Bus Off >> Inspection Repair >> Component Inspection
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Component Inspection

WARNING: This page is about a different variant/trim than selected.

Check internal errors of CAN communication units.

  1. Connect GDS.
  2. IG "ON" and engine "OFF".
  3. Select "DTC Analysis" mode.
  4. Disconnect DDM and monitor DTC to find the cause.
    Fig 1: Body Control Module And Smart Junction Box - Circuit Diagram
    G08314400Courtesy of KIA MOTORS AMERICA, INC.
    Fig 2: Identifying BCM And SJB Connector Terminals End View
    G08314401Courtesy of KIA MOTORS AMERICA, INC.

    *CAN communication units: BCM(Body Control Module), CLU(Cluster), SMK(Smart Key), SJB(Smart Junction Box), PSM (Power Seat Module).

  5. Is the code erased?

    YES 

    • Substitute with a known - good unit and check for proper operation.

      If the problem is corrected, replace the unit and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

    NO 

    • Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.