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Scan Tool Does Not Power Up

  1. Check for battery voltage at Data Link Connector (DLC) terminal No. 16 (Orange wire). See Figure. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short to ground in Orange wire between DLC and CIGAR fuse (15-amp) located in engine wiring harness junction block. Perform appropriate diagnostic system check. See appropriate article for malfunctioning system.
  2. Check for open in Black wire between DLC terminal No. 4 and ground. See DATA LINK CONNECTORS article in WIRING DIAGRAMS. Repair circuit as necessary and perform appropriate diagnostic system check. See appropriate article for malfunctioning system. If ground circuit is okay, go to next step.
  3. Check for poor connections between scan tool and DLC terminals No. 4 and 16. Repair as necessary and perform appropriate diagnostic system check. See appropriate article for malfunctioning system. If no problems are found, go to next step.
  4. Scan tool may be malfunctioning. Check scan tool manual for diagnostic procedures. After repairs, perform appropriate diagnostic system check. See appropriate article for malfunctioning system.
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