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BCM Diagnostic System Check: Testing

  1. Close all doors. Turn ignition switch to OFF position. Remove MALL PGM fuse (10-amp) from instrument panel fuse block. Turn ignition switch to ACC position. BCM will enter feature customization mode. This will cause seat belt indicator light to flash and chime to sound to indicate type of BCM (2, 3 or 4). If BCM is identified, go to next step. If BCM is not identified, go to step 4).
  2. If type of BCM identified in previous step matches vehicle equipment/options, go to next step. If type of BCM identified in previous step does not match equipment/options available for that vehicle, go to step 22).
  3. Within one second, turn ignition switch from ACC position to OFF position, then back to ACC position. BCM will enter diagnostic mode, and will cause seat belt indicator light to flash and chime to sound to indicate any stored DTCs. See BCM DTC DEFINITIONS  under SELF-DIAGNOSTIC SYSTEM. If any DTCs are stored, go to step 23). If no DTCs are stored, go to next step.
  4. Check INT LAMP fuse (10-amp) located in instrument panel fuse block. If fuse is open, go to next step. If fuse is okay, go to step 6).
  5. Replace INT LAMP fuse. Check INT LAMP fuse again. If fuse is open, go to step 24). If fuse is okay, go to next step.
  6. Check PWR LOCK fuse (15-amp) located in instrument panel fuse block. If fuse is open, go to next step. If fuse is okay, go to step 8).
  7. Replace PWR LOCK fuse. Check PWR LOCK fuse again. If fuse is open, go to step 25). If fuse is okay, go to next step.
  8. Check I/P-IGN fuse (10-amp) located in instrument panel fuse block. If fuse is open, go to next step. If fuse is okay, go to step 10).
  9. Replace I/P-IGN fuse. Turn ignition switch to RUN position. Check I/P-IGN fuse again. If fuse is open, go to step 26). If fuse is okay, go to next step.
  10. Check MALL fuse (10-amp) located in instrument panel fuse block. If fuse is open, go to next step. If fuse is okay, go to step 12).
  11. Replace MALL fuse. Turn ignition switch to RUN position. Check MALL fuse again. If fuse is open, go to step 27). If fuse is okay, go to next step.
  12. Turn ignition switch to OFF position. Disconnect BCM Natural 8-pin connector C1. Connect test light between BCM harness connector C terminal "D" (Black wire) and battery. If test light illuminates, go to next step. If test light does not illuminate, go to step 28).
  13. Connect test light between BCM harness connector C1 terminal "G" (Orange wire) and ground. If test light illuminates, go to next step. If test light does not illuminate, go to step 29).
  14. Connect test light between BCM harness connector C1 terminal "H" (Orange wire) and ground. If test light illuminates, go to next step. If test light does not illuminate, go to step 30).
  15. Disconnect BCM Blue 32-pin connector C2. Turn ignition switch to RUN position. Connect test light between BCM harness connector C2 terminal C13 (Pink wire) and ground. If test light illuminates, go to next step. If test light does not illuminate, go to step 31).
  16. Leave test light connected as indicated in previous step. Turn ignition switch to OFF position. If test light does not illuminate, go to next step. If test light illuminates, go to step 32).
  17. Turn ignition switch to RUN position. Connect test light between BCM harness connector C terminal D4 (Yellow wire) and ground. If test light illuminates, go to next step. If test light does not illuminate, go to step 33).
  18. Leave test light connected as indicated in previous step. Turn ignition switch to OFF position. If test light does not illuminate, go to next step. If test light illuminates, go to step 34).
  19. Connect test light between BCM harness connector C terminal C9 (Orange/Black wire) and ground. If test light does not illuminate, go to next step. If test light illuminates, go to step 35).
  20. Leave test light connected as indicated in previous step. Reinstall MALL PGM fuse. Turn ignition switch to ACC or ON position. If test light illuminates, go to next step. If test light does not illuminate, go to step 36).
  21. Turn ignition switch to OFF position. Reconnect BCM connectors C1 and C2. Ensure all doors are closed. Remove MALL PGM (10-amp) from instrument panel fuse block. Turn ignition switch to ACC position. Seat belt indicator light should flash and chime should sound to indicate type of BCM (2, 3 or 4). If BCM is identified, go to step 38). If BCM is not identified, go to step 37).
  22. Replace BCM with appropriate BCM type. See REMOVAL & INSTALLATION. Go to step 1).
  23. Go to appropriate DTC test. Diagnose and repair as necessary. After repairs are complete, go to step 1).
  24. Repair short to ground in circuit No. 240 (Orange wire) between BCM and instrument panel fuse block. Go to step 1).
  25. Repair short to ground in circuit No. 1540 (Orange wire) between BCM and instrument panel fuse block. Go to step 1).
  26. Repair short to ground in circuit No. 39 (Pink wire) between BCM and instrument panel fuse block. Go to step 1).
  27. Repair short to ground in circuit No. 443 (Yellow wire) between BCM and instrument panel fuse block. Go to step 1).
  28. Repair poor connection or open in circuit No. 1550 (Black wire) between BCM and ground. Go to step 1).
  29. Repair poor connection or open in circuit No. 240 (Orange wire) between BCM and instrument panel fuse block. Go to step 1).
  30. Repair poor connection or open in circuit No. 1540 (Orange wire) between BCM and instrument panel fuse block. Go to step 1).
  31. Repair poor connection or open in circuit No. 39 (Pink wire) between BCM and instrument panel fuse block. Go to step 1).
  32. Repair short to voltage in circuit No. 39 (Pink wire) between BCM and instrument panel fuse block. Go to step 1).
  33. Repair poor connection or open in circuit No. 443 (Yellow wire) between BCM and instrument panel fuse block. Go to step 1).
  34. Repair short to voltage in circuit No. 443 (Yellow wire) between BCM and instrument panel fuse block. Go to step 1).
  35. Repair short to voltage in circuit No. 1445 (Orange/Black wire) between BCM and instrument panel fuse block. Go to step 1).
  36. Repair poor connection or open in circuit No. 1445 (Orange/Black wire) between BCM and instrument panel fuse block. Go to step 1).
  37. Check for poor connections at BCM connectors. Repair as necessary, and go to step 1). If connections are okay, replace BCM. See REMOVAL & INSTALLATION  . Go to step 1).
  38. If you were sent to this test from a DTC test, return to appropriate DTC test. If you were not sent to this test from a DTC test, system is operating properly.
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