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BCM Diagnostic System Check: Testing

  1. Connect scan tool to Data Link Connector (DLC). If scan tool powers up, go to next step. If scan tool does not power up, go to SCAN TOOL DOES NOT POWER UP  .
  2. Turn ignition switch to RUN position. Using scan tool, attempt to establish communication with BCM. If scan tool communicates with BCM, go to next step. If scan tool does not communicate with BCM, go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  .
  3. Select BCM display DTCs function. If any DTCs exist, go to next step. If no DTCs exist go to appropriate system starting point for related system.
  4. If any communication DTCs exist (DTCs beginning with a "U"), go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  . If no communication DTCs exist, go to next step.
  5. If DTC B1000 exists, go to DTC B1000: ECU MALFUNCTION  under DIAGNOSTIC TESTS. See BCM DTC DEFINITIONS  table under SELF-DIAGNOSTIC SYSTEM. If DTC B1000 or B1013 do not exist, go to next step.
  6. If DTCs B1339, B1349 or B1440 exist, perform appropriate test under DIAGNOSTIC TESTS  . See BCM DTC DEFINITIONS  table under SELF-DIAGNOSTIC SYSTEM. If DTCs other than B1339, B1349 or B1440 exist, go to appropriate system starting point for related system.