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BCM Diagnostic System Check: Testing

  1. Turn ignition switch to LOCK position. Connect scan tool. Turn ignition switch to RUN position. Using scan tool, attempt to establish communication with BCM. If scan tool communicates with BCM, go to step 15). If scan tool does not communicate with BCM, go to next step.
  2. Using scan tool, attempt to establish communication with Powertrain Control Module (PCM), Instrument Panel Cluster (IPC) and Electronic Brake Traction Control Module (EBTCM). If scan tool communicates with other systems, go to next step. If scan tool does not communicate with other systems, go to step 9).
  3. Check ABS-BCM fuse (10-amp), located in instrument panel fuse block. If fuse is blown, go to next step. If fuse is not blown, go to step 5).
  4. Replace ABS-BCM fuse. Turn ignition switch to LOCK, then to RUN position. Check ABS-BCM fuse again. If fuse is blown, go to step 10). If fuse is not blown, go to next step.
  5. Turn ignition switch to LOCK position. Disconnect BCM Natural 10-pin connector C3. Connect test light between ground and BCM harness connector C3, terminal "B" (Orange wire). If test light illuminates, go to next step. If test light does not illuminate, go to step 11).
  6. Connect test light between BCM harness connector C3, terminals "B" (Orange wire) and "D" (Black wire). If test light illuminates, go to next step. If test light does not illuminate, go to step 12).
  7. Disconnect BCM Pink 24-pin connector C2. Disconnect scan tool. Using DVOM, check resistance between BCM connector C2, terminal B5 (Light Green wire) and Data Link Connector (DLC) terminal No. 2 (Purple wire). If resistance is less than 2 ohms, go to next step. If resistance is not less than 2 ohms, go to step 13).
  8. Turn ignition switch to LOCK position. Reinstall all components or connectors. Connect scan tool. Turn ignition switch to RUN position. Using scan tool, attempt to establish communication with BCM. If scan tool communicates with BCM, go to step 15). If scan tool does not communicate with BCM, go to step 14).
  9. Scan tool is unable to communicate with vehicle systems because of a malfunction in class 2 data line. Go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DATA LINE  . After malfunction is repaired, go to step 1).
  10. Repair short to ground in Orange wire between BCM connector C3 and instrument panel fuse block. Go to step 1).
  11. Repair poor connection or open in Orange wire between BCM connector C3 and instrument panel fuse block. Go to step 1).
  12. Repair poor connection or open in Black wire between BCM connector C3 and ground. Go to step 1).
  13. Repair poor connection or open in Light Green or Purple wire between BCM connector C3, splice pack SP205 and DLC. Go to step 1).
  14. Replace BCM. See REMOVAL & INSTALLATION  . Reprogram BCM. See BCM PROGRAMMING  . Go to step 1).
  15. Using scan tool, check for current and history BCM DTCs. See BCM DTC DEFINITIONS  under SELF-DIAGNOSTIC SYSTEM. If no DTCs exist, system is operating properly. If any current or history BCM DTC exists, go to appropriate DTC test. If more than one DTC exists, start with lowest number DTC first. After all current and history DTCs have been diagnosed and repaired, go to step 1).
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