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Diagnostic Procedures

  1. Turn ignition off. Using DVOM connected to ground, backprobe Data Link Connector (DLC) terminal No. 16 (Orange wire). See WIRING DIAGRAMS  . If voltage reading is 9-14 volts, go to next step. If voltage reading is not 9-14 volts, go \to step 14).
  2. Using DVOM, check voltage between battery positive and DLC terminal No. 5 (Black wire). If voltage reading is 9-14 volts, go to next step. If voltage reading is not 9-14 volts, go to step 15).
  3. Check voltage between battery positive and DLC terminal No. 4 (Black wire). If voltage reading is 9-14 volts, go to next step. If voltage reading is not 9-14 volts, go to step 12).
  4. Using another vehicle, attempt to establish communication with the same system. If communication can be established, go to next step. If communication cannot be established, check for faulty scan tool. Replace scan tool and recheck system operation.
  5. Check scan tool for proper connection to DLC in original vehicle. If connection is good, go to next step. If communication cannot be established, go to step 16).
  6. Turn ignition switch to RUN position. Using scan tool, attempt to establish communication with air bag sensing and diagnostic module (UART serial data line). If communication can be established, go to next step. If communication cannot be established, go to step 8).
  7. Turn ignition off. Disconnect air bag restraint and diagnostic module harness connector. Check harness connector connections. If connections are good, go to step 13). If connections are faulty, repair connections and recheck system operation.
  8. Turn ignition off. Disconnect air bag restraint and diagnostic module harness connector. Using DVOM, check resistance between DLC terminals No. 9 (Tan wire) and No. 5 (Black wire). If reading is infinite, go to next step. If reading is not infinite, repair short to ground in circuit. After repairs, recheck system operation.
  9. Turn ignition switch to RUN position. Check voltage between DLC terminals No. 5 (Black wire) and No. 9 (Tan wire). If any voltage is present, repair short to voltage on circuit. After repairs, recheck system operation. If no voltage is present, go to next step.
  10. Turn ignition off. Check resistance between DLC terminal No. 9 (Tan wire) and air bag restraint sensing and diagnostic module harness connector terminal No. 5 (Tan wire). If resistance is 0-5 ohms, go to next step. If resistance is not 0-5 ohms, repair poor connection or open in circuit. After repairs, recheck system operation.
  11. Reconnect air bag restraint sensing and diagnostic module harness connector. Turn ignition switch to RUN position. Using scan tool, attempt to establish communications with air bag restraint sensing and diagnostic module. If communication can be established, system is okay. If communication cannot be established, go to step 13).
  12. Check and ensure ground connection to DLC terminal No. 4 (Black wire) is clean and tight. Repair as necessary. After repairs, recheck system operation. If connection is good, recheck system operation.
  13. Turn ignition off. Check for power, ground and proper connection to air bag restraint sensing and diagnostic module. Repair as necessary. If connections are okay, replace module. After replacing module, recheck system operation.
  14. Check and ensure RADIO-HVAC fuse is good. If fuse is good, repair poor connection or open in circuit to fuse block. After repairs, recheck system operation. If fuse is open, replace fuse. After replacing fuse, recheck system operation.
  15. Check and ensure ground connection to DLC terminal No. 5 (Black wire) is clean and tight. Repair as necessary. After repairs, recheck system operation.
  16. Repair DLC terminal No. 9 or reconnect scan tool as necessary. Recheck system operation.
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