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DTC 12: Diagnostic System Check: Testing

  1. Turn ignition switch to RUN position. If SECURITY indicator illuminates, go to next step. If SECURITY indicator does not illuminate, go to step 3).
  2. Attempt to enter BCM diagnostic mode. If SECURITY indicator flashes DTCs, system is operating properly.
  3. Turn ignition switch to OFF position. Disconnect BCM Blue, 32-pin connector C3. Connect a fused jumper wire between BCM connector C3, terminal C12 (Gray wire) and ground. If SECURITY indicator illuminates, go to next step. If SECURITY indicator does not illuminate, go to step 5).
  4. Check for a poor connection at BCM connector C3 terminal C12 (Gray wire). Repair as necessary. If connection is okay, replace BCM. See REMOVAL & INSTALLATION  .
  5. Disconnect instrument cluster Black 34-pin connector. Connect a test light between instrument cluster terminal A13 (Orange wire) and ground. If test light illuminates, go to next step. If test light does not illuminate, go to step 7).
  6. Check for an open or poor connection in Gray wire between instrument cluster and BCM. If circuit is okay, service instrument cluster. See INSTRUMENT PANEL article.
  7. Repair open in Orange wire between instrument cluster and instrument panel fuse block.
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