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Home >> Pontiac >> 1999 >> Grand Prix SE, 3.1 M >> Repair and Diagnosis >> Body & Frame >> Body, Cab Control Systems >> Body Control Modules >> System Tests >> BCM Diagnostic System Check >> Testing
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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. Turn ignition switch from ACC position to OFF position, then back to ACC position within one second. 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  table 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 ON 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 ON 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 C2 terminal "D" (Black wire) and battery. See WIRING DIAGRAMS  . See Figure . If test light comes on, go to next step. If test light does not come on, go to step  28 .
  13. Connect test light between BCM harness connector C1 terminal "G" (Orange wire) and ground. If test light comes on, go to next step. If test light does not come on, go to step  29 .
  14. Connect test light between BCM harness connector C1 terminal "H" (Orange wire) and ground. If test light comes on, go to next step. If test light does not come on, go to step  30 .
  15. Disconnect BCM Blue 32-pin connector C2. Turn ignition switch to ON position. Connect test light between BCM harness connector C2 terminal C13 (Pink wire) and ground. If test light comes on, go to next step. If test light does not come on, 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 come on, go to next step. If test light comes on, go to step  32 .
  17. Turn ignition switch to ON position. Connect test light between BCM harness connector C2 terminal D4 (Yellow wire) and ground. If test light comes on, go to next step. If test light does not come on, 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 come on, go to next step. If test light comes on, go to step  34 .
  19. Connect test light between BCM harness connector C2 terminal C9 (Orange/Black wire) and ground. If test light does not come on, go to next step. If test light comes on, 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 comes on, go to next step. If test light does not come on, 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 BODY CONTROL MODULE (BCM)  under REMOVAL & INSTALLATION. After repairs, go to step  1 .
  23. Go to appropriate DTC test under DIAGNOSTIC TESTS  . After repairs are complete, go to step  1 .
  24. Repair short to ground in Orange wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  25. Repair short to ground in Orange wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  26. Repair short to ground in Pink wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  27. Repair short to ground in Yellow wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  28. Repair poor connection or open in Black wire between BCM and ground. After repairs, go to step  1 .
  29. Repair poor connection or open in Orange wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  30. Repair poor connection or open in Orange wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  31. Repair poor connection or open in Pink wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  32. Repair short to voltage in Pink wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  33. Repair poor connection or open in Yellow wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  34. Repair short to voltage in Yellow wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  35. Repair short to voltage in Orange/Black wire between BCM and instrument panel fuse block. After repairs, go to step  1 .
  36. Repair poor connection or open in Orange/Black wire between BCM and instrument panel fuse block. After repairs, 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 BODY CONTROL MODULE (BCM)  under REMOVAL & INSTALLATION. After repairs, 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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